Voicing

I want to try to distill here the approach and philosophy I have developed over the years, taking bits and pieces of lots of people, and which I find works consistently well for me. Just to start off, I will comment that I think Steinway evolved into using lacquer without ever developing a consistent "official" approach until fairly recently (really within the last 15 years or so), and I have tried that approach and disagree with it.

Let's start with "philosophy," or at least a good mental picture of what we are dealing with. In order to produce power and brilliance, any hammer needs to have a pretty high degree of density and stiffness in the area between the tip of the hammer molding and the surface of the crown that touches the strings. That is a given that is true of every hammer. If you don't need brilliance, you can have less density to start with, but for concert instruments (especially ones used for concertos and in large halls) you need that brilliance and therefore that density/stiffness.

The "hard pressed" hammer has density, and we typically leave that density alone in that special area of the hammer, leaving that pointed triangle of dense felt untouched by needles (except at the very surface). For a softer hammer, we need to add stiffness by adding a hardener. So where does the hardener need to go without question? Precisely between the tip of the molding and the surface. However you get the lacquer into the hammer felt, you have to have lacquer in that area to get power and brilliance, period. You can do that by pouring lacquer over the crowns and saturating the entire hammer if you want to, or by putting the hammers crown down in a trough and adding lacquer to the trough. But then you have lacquer in essentially all the felt of the hammer, making the whole structure stiff.

The stiffness in the "magic triangle" does need some support, but it doesn't need the whole hammer to be saturated, at least in my experience. All the lacquer that is really needed is a circle of lacquer around the point of the molding, leaving the shoulders flexible. So I strongly believe that applying lacquer to the sides of the hammers, individually, aiming right at the point of the molding, is the best way to go. One or maybe two applications (more than that becomes problematic for penetration). That should provide the power you need, and if more brilliance is needed a surface application to the crown with provide it. 

Now, what about needling? The official procedure, established by Ron Coners (I don't know if it has been altered in the past 3 - 4 years as I have been out of touch) states that single needle deep, right at the center of the crown, perpendicular into the hammer felt, is all that you need. I disagree.

I have found, after years of experimenting, that I get the best results from "standard needling practice": three needle tool, 10 mm #6 or so needles, deep into shoulders in the basic pattern outlined in the Renner voicing handbook, ending up by leaving that point of the triangle on the top, or maybe you picture a diamond shape surrounding the tip of the molding. This does assume the hammers have not been over-lacquered. This kind of voicing gives a consistent rise in timbre throughout the dynamic range, just as it does in a hard-pressed hammer. The key is to do things consistently from hammer to hammer, and do the bare minimum of "custom" work to even things out. A pattern of insertions that staggers from side to side of the hammer, as it moves up from low shoulder to crown, will result in an evenly resilient result. I find that 7 - 10 insertions per side is a general average - while that will vary depending on degree of lacquering you encounter. If the needles won't go in due to too much lacquer, you need to wash lacquer out first. Touch up to even out is done with single needle, and should be right at the crown (that is all that should be necessary).

So that is a fairly short version of what I think works in the real world, without a lot of fussing and hassle. When hammers are set up that way, shift voicing can be quite even throughout the dynamic range with the shift voicing technique I outlined in the Fazioli shift set up thread (also assuming level strings and good mating, of course).

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------

Lacquer application to the area under the crown is something I've always advocated for the reasons you have cited. Moreover, one of the things done in a tensioned or pressed hammer (those aren't always the same thing, btw, pressed hammers often lack adequate tension) is to release some tension from the "spring" (the hammer is a non-linear spring when operating successfully--it compresses and increases in resistance at an ever increasing rate). The hammer needs to compress and so if the spring is compressed completely then it can't compress anymore. Needling the shoulders and the upper part of the hammer releases some tension and the spring opens up. In fact, we like to refer to shoulder needling as opening up the hammer. Opening up the spring will usually require some needling in the upper part of the hammer as well. In fact, it is mostly in the upper part (the 1:30 - 12:00, or just short of 12, where opening up really gives us a tonal change. Needling lower, in the 3 - 1:30 range (on both sides) simply lays the groundwork. However, not all hammers have tension, some are more density driven. If the hammer lacks tension and then one needs to create a density gradient to compensate for the spring that the hammer will never have. In that case, needling closer to the crown, still avoiding the inverted triangle if possible, gives the area between the strike point and the tip of the molding more room to move, as it were, more flexibility. If the hammer is too soft then the density gradient doesn't achieve this non-linear spring quality, it doesn't increase in density as we push up the dynamic ladder, at least not enough. The more we push the more the hammer collapses absorbing energy (loss of power) and damping upper partials. So we need to reinforce the are under the crown. We still want some flexibility left in the shoulder of the hammer similar to what we do in a non-lacquered hammer to get it to open up. The amount and strength of the lacquer will vary depending on how much rigid we need to make the internal structure of the hammer beneath the strike point. Since the lacquer can only be applied in the form of a circle (applications trying t create a triangle shape don't work) then it is altogether likely that the needling in the upper quadrant of the hammer (on both sides) will be necessary in order to insure that we still have flexibility there. Needling straight down through the strike point creates a soft center with rigid surrounding and supporting areas. What we want is a more rigid center (straight down through the strike point) with increasing flexible supporting areas from the inside moving out. Thus the straight down through the crown voicing is to be avoided unless absolutely necessary to attack crystals that tend to form when using furniture style off the shelf lacquer. By using soft setting lacquers, those that remain more flexible as they cure (these lacquers would be totally inappropriate for your dining room table) you can avoid those problems. The lacquer currently being sold by Pianotek (Hammer Lac) is this type of lacquer, i.e., soft setting. Paint store lacquers are not appropriate for this type of use. Of course lacquer is an extreme measure, required when the consistency of the hammer has failed or the appropriate hammer matching (hammer tension, density, weight, profile) to the belly is poorly done. This was at the heart of the two classes I gave at WestPacIII, Choosing hammers, or hammer matching really, and the Principles of voicing covering both Needle and Lacquer techniques. Of course there are other issues than those I've outline here but there was hardly time in two 90 minute sessions there to cover and communicate it adequately. This will have to do here for now. Forgive typos or awkward constructions, no time to proof right now. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Friday, March 15, 2013 11:34 AM To: David Love Subject: Voicing: lacquer voicing I want to try to distill here the approach and philosophy I have developed over the years, taking bits and pieces of lots of people, and which I find works consistently well for me. Just to start off, I will comment that I think Steinway evolved into using lacquer without ever developing a consistent "official" approach until fairly recently (really within the last 15 years or so), and I have tried that approach and disagree with it. Let's start with "philosophy," or at least a good mental picture of what we are dealing with. In order to produce power and brilliance, any hammer needs to have a pretty high degree of density and stiffness in the area between the tip of the hammer molding and the surface of the crown that touches the strings. That is a given that is true of every hammer. If you don't need brilliance, you can have less density to start with, but for concert instruments (especially ones used for concertos and in large halls) you need that brilliance and therefore that density/stiffness. The "hard pressed" hammer has density, and we typically leave that density alone in that special area of the hammer, leaving that pointed triangle of dense felt untouched by needles (except at the very surface). For a softer hammer, we need to add stiffness by adding a hardener. So where does the hardener need to go without question? Precisely between the tip of the molding and the surface. However you get the lacquer into the hammer felt, you have to have lacquer in that area to get power and brilliance, period. You can do that by pouring lacquer over the crowns and saturating the entire hammer if you want to, or by putting the hammers crown down in a trough and adding lacquer to the trough. But then you have lacquer in essentially all the felt of the hammer, making the whole structure stiff. The stiffness in the "magic triangle" does need some support, but it doesn't need the whole hammer to be saturated, at least in my experience. All the lacquer that is really needed is a circle of lacquer around the point of the molding, leaving the shoulders flexible. So I strongly believe that applying lacquer to the sides of the hammers, individually, aiming right at the point of the molding, is the best way to go. One or maybe two applications (more than that becomes problematic for penetration). That should provide the power you need, and if more brilliance is needed a surface application to the crown with provide it. Now, what about needling? The official procedure, established by Ron Coners (I don't know if it has been altered in the past 3 - 4 years as I have been out of touch) states that single needle deep, right at the center of the crown, perpendicular into the hammer felt, is all that you need. I disagree. I have found, after years of experimenting, that I get the best results from "standard needling practice": three needle tool, 10 mm #6 or so needles, deep into shoulders in the basic pattern outlined in the Renner voicing handbook, ending up by leaving that point of the triangle on the top, or maybe you picture a diamond shape surrounding the tip of the molding. This does assume the hammers have not been over-lacquered. This kind of voicing gives a consistent rise in timbre throughout the dynamic range, just as it does in a hard-pressed hammer. The key is to do things consistently from hammer to hammer, and do the bare minimum of "custom" work to even things out. A pattern of insertions that staggers from side to side of the hammer, as it moves up from low shoulder to crown, will result in an evenly resilient result. I find that 7 - 10 insertions per side is a general average - while that will vary depending on degree of lacquering you encounter. If the needles won't go in due to too much lacquer, you need to wash lacquer out first. Touch up to even out is done with single needle, and should be right at the crown (that is all that should be necessary). So that is a fairly short version of what I think works in the real world, without a lot of fussing and hassle. When hammers are set up that way, shift voicing can be quite even throughout the dynamic range with the shift voicing technique I outlined in the Fazioli shift set up thread (also assuming level strings and good mating, of course). ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

Let me add to that: The difference between hammers that have tension and those that don’t (hammers that are pressed into submission and by virtue of the prepressing process or other pressing protocols remove any and all traces of tension) must create a density gradient as a substitute for flexibility and resilience. In the worst cases, where flexibility cannot be created even by needling close(r) to the strike point triangle, which you will have to do with non tensioned hammers, cross stitching under the crown in order to create a density gradient will be necessary. How much and how deep will depend on the density and consistency of the hammer as you move progressively deeper. Judging what kind of hammer you have can be tricky by visual inspection, but the way that the hammer reacts as you move with needles toward the strike point will tell you a lot. Tensioned hammers will be more reactive and you will see tonal changes occurring when needling farther away from the SP. A reason to tread cautiously. Hammers of a density driven nature will be less stable (read get louder faster) than will tensioned hammers because in a tensioned hammer there as a flexibility built into the hammer, a quality of flexible resilience derived from the tension itself. Density driven hammers have no such spring to them and will pack down purely as a function of ongoing compaction to a greater of lesser degree depending on the balance of tension/density. Most hammers have some tension, some have none and some have a lot. Lacquered hammers, by the time you are done lacquering them, especially to the extent that a D hammer needs to be lacquered, have little tension left in them. The act of lacquering is helping to create your artificial, non-linear spring by creating the desired density gradient but this time from the not dense enough starting point. Further, the stiffening of the fibers also makes them less flexible. Under load they will eventually have a tendency to fracture rather than flex as hard setting lacquers (and basically all lacquers) make them more brittle. Their stability will be that of a density driven hammer rather than a tension driven hammer. Just an aside. Every needle stitch you put in a tensioned hammer removes tension to some degree. Eventually, even tensioned hammers become density driven hammers, some sooner than later due to the number of stitches required out of the box, often the result of poor impedance matching in the first place. Put the hammer on there that needs the least amount of hammer abuse. And make no mistake, it is all abuse. David Love www.davidlovepianos.com
Original Message----- From: David Love [mailto:noreply@egroups.ptg.org] Sent: Friday, March 15, 2013 1:49 PM To: David Love Subject: Voicing : RE: lacquer voicing Lacquer application to the area under the crown is something I've always advocated for the reasons you have cited. Moreover, one of the things done in a tensioned or pressed hammer (those aren't always the same thing, btw, pressed hammers often lack adequate tension) is to release some tension from the "spring" (the hammer is a non-linear spring when operating successfully--it compresses and increases in resistance at an ever increasing rate). The hammer needs to compress and so if the spring is compressed completely then it can't compress anymore. Needling the shoulders and the upper part of the hammer releases some tension and the spring opens up. In fact, we like to refer to shoulder needling as opening up the hammer. Opening up the spring will usually require some needling in the upper part of the hammer as well. In fact, it is mostly in the upper part (the 1:30 - 12:00, or just short of 12, where opening up really gives us a tonal change. Needling lower, in the 3 - 1:30 range (on both sides) simply lays the groundwork. However, not all hammers have tension, some are more density driven. If the hammer lacks tension and then one needs to create a density gradient to compensate for the spring that the hammer will never have. In that case, needling closer to the crown, still avoiding the inverted triangle if possible, gives the area between the strike point and the tip of the molding more room to move, as it were, more flexibility. If the hammer is too soft then the density gradient doesn't achieve this non-linear spring quality, it doesn't increase in density as we push up the dynamic ladder, at least not enough. The more we push the more the hammer collapses absorbing energy (loss of power) and damping upper partials. So we need to reinforce the are under the crown. We still want some flexibility left in the shoulder of the hammer similar to what we do in a non-lacquered hammer to get it to open up. The amount and strength of the lacquer will vary depending on how much rigid we need to make the internal structure of the hammer beneath the strike point. Since the lacquer can only be applied in the form of a circle (applications trying t create a triangle shape don't work) then it is altogether likely that the needling in the upper quadrant of the hammer (on both sides) will be necessary in order to insure that we still have flexibility there. Needling straight down through the strike point creates a soft center with rigid surrounding and supporting areas. What we want is a more rigid center (straight down through the strike point) with increasing flexible supporting areas from the inside moving out. Thus the straight down through the crown voicing is to be avoided unless absolutely necessary to attack crystals that tend to form when using furniture style off the shelf lacquer. By using soft setting lacquers, those that remain more flexible as they cure (these lacquers would be totally inappropriate for your dining room table) you can avoid those problems. The lacquer currently being sold by Pianotek (Hammer Lac) is this type of lacquer, i.e., soft setting. Paint store lacquers are not appropriate for this type of use. Of course lacquer is an extreme measure, required when the consistency of the hammer has failed or the appropriate hammer matching (hammer tension, density, weight, profile) to the belly is poorly done. This was at the heart of the two classes I gave at WestPacIII, Choosing hammers, or hammer matching really, and the Principles of voicing covering both Needle and Lacquer techniques. Of course there are other issues than those I've outline here but there was hardly time in two 90 minute sessions there to cover and communicate it adequately. This will have to do here for now. Forgive typos or awkward constructions, no time to proof right now. David Love www.davidlovepianos.com

And yet one more thing (this just never ends): Filing also removes tension. When hammers are folded over the molding the outer layers are stretched but the felt next to the molding is compressed. So as you go deeper into the hammer you move from tension to compression. Removing the outer layers of the hammer, therefore, is removing the layers with the highest tension. Once you remove outer layers are the inner layers allowed to expand thereby moving in the direction of compression to tension? I don't know the answer to that but it would be interesting to know and to what extent. My sense (from what I hear in the piano) is that if there is an increase in tension in that way it's not as much as the tension that was on the outer layers to begin with. Nevertheless, when making hammers, it's best to skive from the inside to the proper dimension and then stretch the felt rather than stretch the felt and then sand to the proper dimension. Similarly, filing to the reduce the profile once the hammers are already installed in the piano might give you greater effective density by moving the strike point closer to the molding, but it is also removing tension. Better to get it right at the start. Unless, of course, you think that tension is a quality that you don't want in hammers. So far, I am not in that camp. David Love www.davidlovepianos.com
Original Message----- From: David Love [mailto:noreply@egroups.ptg.org] Sent: Friday, March 15, 2013 2:19 PM To: David Love Subject: Voicing : RE: lacquer voicing Let me add to that: The difference between hammers that have tension and those that don’t (hammers that are pressed into submission and by virtue of the prepressing process or other pressing protocols remove any and all traces of tension) must create a density gradient as a substitute for flexibility and resilience. In the worst cases, where flexibility cannot be created even by needling close(r) to the strike point triangle, which you will have to do with non tensioned hammers, cross stitching under the crown in order to create a density gradient will be necessary. How much and how deep will depend on the density and consistency of the hammer as you move progressively deeper. Judging what kind of hammer you have can be tricky by visual inspection, but the way that the hammer reacts as you move with needles toward the strike point will tell you a lot. Tensioned hammers will be more reactive and you will see tonal changes occurring when needling farther away from the SP. A reason to tread cautiously. Hammers of a density driven nature will be less stable (read get louder faster) than will tensioned hammers because in a tensioned hammer there as a flexibility built into the hammer, a quality of flexible resilience derived from the tension itself. Density driven hammers have no such spring to them and will pack down purely as a function of ongoing compaction to a greater of lesser degree depending on the balance of tension/density. Most hammers have some tension, some have none and some have a lot. Lacquered hammers, by the time you are done lacquering them, especially to the extent that a D hammer needs to be lacquered, have little tension left in them. The act of lacquering is helping to create your artificial, non-linear spring by creating the desired density gradient but this time from the not dense enough starting point. Further, the stiffening of the fibers also makes them less flexible. Under load they will eventually have a tendency to fracture rather than flex as hard setting lacquers (and basically all lacquers) make them more brittle. Their stability will be that of a density driven hammer rather than a tension driven hammer. Just an aside. Every needle stitch you put in a tensioned hammer removes tension to some degree. Eventually, even tensioned hammers become density driven hammers, some sooner than later due to the number of stitches required out of the box, often the result of poor impedance matching in the first place. Put the hammer on there that needs the least amount of hammer abuse. And make no mistake, it is all abuse. David Love www.davidlovepianos.com

Thanks for those detailed posts, David. Very interesting and insightful. However, they are a little tangential to the topic, which is how you should proceed in voicing a lacquered hammer. It is all very well to explain why you shouldn't choose a hammer that needs to be lacquered, but the practical fact is that as piano technicians, particularly as technicians who service concert venues of one sort or other, the hammers are often to almost always lacquered hammers.

So we need to know what to do, what works. The fact of the matter is that lacquered hammers can be made more than just acceptable, as evidenced by the broad range of people who accept them - and I am among them as a pianist. I can't honestly say I prefer one type of hammer over the other in some absolute way. I do prefer the wider range of tone color in a well chosen, well-prepped non-lacquered tensioned hammer, but that is not an absolute preference. There are plenty of the same non-lacquered hammer that I don't prefer, depending usually on prep (and things get so complex so fast, with so many other variables, that one can't really make any blanket statements that are meaningful).

In any case, what I really want to get at here is a discussion of what procedures seem to be best in the original set up of a set of lacquered hammers and in their upkeep over time. That is something I deal with on a weekly basis, it's a big part of my job. There are thousands of Steinways with lacquered hammers out there that need care, so we need to know how to give it.

BTW, I agree with your last statement: "Put the hammer on there that needs the least amount of hammer abuse. And make no mistake, it is all abuse."  -  although with the caveat that I don't know that any hammer sounds better "out of the box" than it does when opened up a little, so maybe I would temper that statement to say that the initial opening up is, if well executed, not in fact "abuse" but a necessary procedure to adjust the felt after pressing for optimum tone gradient.

And I would add that, with lacquered hammers, the amount of lacquer should be "just enough." Too much lacquer is another kind of hammer abuse. When it is "just enough," the hammer can, IMO, have resilience and behave pretty analogously to the tensioned hammer, again with minimum needle insertions done with consistency and care. That, at any rate, is what my experience has seemed to teach me.


-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-15-2013 17:16
From: David Love
Subject: lacquer voicing

Let me add to that:

The difference between hammers that have tension and those that don’t (hammers that are pressed into submission and by virtue of the prepressing process or other pressing protocols remove any and all traces of tension) must create a density gradient as a substitute for flexibility and resilience. In the worst cases, where flexibility cannot be created even by needling close(r) to the strike point triangle, which you will have to do with non tensioned hammers, cross stitching under the crown in order to create a density gradient will be necessary. How much and how deep will depend on the density and consistency of the hammer as you move progressively deeper.

Judging what kind of hammer you have can be tricky by visual inspection, but the way that the hammer reacts as you move with needles toward the strike point will tell you a lot. Tensioned hammers will be more reactive and you will see tonal changes occurring when needling farther away from the SP. A reason to tread cautiously.

Hammers of a density driven nature will be less stable (read get louder faster) than will tensioned hammers because in a tensioned hammer there as a flexibility built into the hammer, a quality of flexible resilience derived from the tension itself. Density driven hammers have no such spring to them and will pack down purely as a function of ongoing compaction to a greater of lesser degree depending on the balance of tension/density. Most hammers have some tension, some have none and some have a lot. Lacquered hammers, by the time you are done lacquering them, especially to the extent that a D hammer needs to be lacquered, have little tension left in them. The act of lacquering is helping to create your artificial, non-linear spring by creating the desired density gradient but this time from the not dense enough starting point. Further, the stiffening of the fibers also makes them less flexible. Under load they will eventually have a tendency to fracture rather than flex as hard setting lacquers (and basically all lacquers) make them more brittle. Their stability will be that of a density driven hammer rather than a tension driven hammer.

Just an aside. Every needle stitch you put in a tensioned hammer removes tension to some degree. Eventually, even tensioned hammers become density driven hammers, some sooner than later due to the number of stitches required out of the box, often the result of poor impedance matching in the first place.

Put the hammer on there that needs the least amount of hammer abuse. And make no mistake, it is all abuse.

David Love
www.davidlovepianos.com

It was slightly tangential as I think your procedures did a good job of covering how best to work with a lacquered hammer. I agree with many of your suggestions although how far the hammer should shift remains a point of debate, I prefer to have the pedal be able to shift off the left string if needed. Let the pianist decide and control that but give them the option. If they don't prefer that then reset it. It's just the turn of a stop screw. The exception to that would be when overshifting drives the hammer into the adjacent note. Then you are limited. Otherwise I basically agree with what you outlined. It is not tangential in the sense that people are choosing to replace hammers with those that need to be lacquered. There is reason to consider avoiding the problems associated with lacquer both in the short and long term. If we are skilled piano technicians we can make anything sound good. That's our job and we are faced with that dilemma all the time. We may have to rely on our arsenal of extreme voicing procedures and there's a virtual cottage industry out there with all kinds of acceptable methods now being taught at conventions such as pliers, dremel tools, snuggle, alcohol, shellac, steam and, yes, lacquer. There are also short cuts designed to side step the foundational procedures such as the recent "angel shot" craze. That's a different thing, however, from discussing what makes a hammer function properly or what our target should be. We get used to things, for better or for worse, and come to accept them as the norm, or even the goal. The lacquer procedure itself arose in conjunction with a failed hammer, it wasn't a preplanned design. We shouldn't forget that. I wasn't suggesting that hammers sound better out of the box. Most of the hammers we get today don't sound better out of the box. They almost all need opening up (or a careful manipulation of the density gradient) to a greater or lesser degree--mostly greater. That's the current state of hammer making for some reason. I consider it a bad habit that we can't seem to break. The problem lies to some degree with certain felt making practices. But most of the blame falls on the hammer makers. They are too often simply doing things that they shouldn't. One thing the quality felt makers will tell you: better felt suffers more under bad procedures than poorer felt. It's not enough that the felt is of high quality to start with. It's easy to ruing a good piece of felt. Those that don’t need a lot of opening up are the ones we are talking about, the ones that need an increase in density, a closing up, as it were, thus lacquer. There are some exceptions but unless careful profiling is done with those hammers (preferably before they reach the press) they will have the opposite problem, inadequate resistance to compression and we end up adding material to stiffen or densify (is that a word?) the felt. The density/profile (thickness of the felt over the wood molding) relationship is very critical and no one is really talking about it, well, except me. Lower density felts (or lower density pressings) need lower profiles, period. Higher density felts or felts with inadequate tension (or both as is often the case) are usually served better by higher profiles. There is never a reason for a high profile/low density relationship and never a reason for a low profile/high density relationship. In the first case you are destined to add stiffness and density chemically because there is no other way to get the non-linear spring effect. Of course you can file them but that has other ramifications, as I outlined previously. If the hammers are already hung then the kind of filing often required will screw up your regulation, bore distance and create other problems. The more "stuff" you add the more problems you have with unwanted noise, lost resilience, poor wear and development--the classic NY D hammer. In the second case, you don't have enough material to open up. The amount of needling needed in a low profile/high density hammer will necessarily destroy tension and turn the hammer into a density gradient driven hammer except that the low profile gives you an inadequate amount of material for the kind of progressive dynamic curve that you want and also impacts the stability--it packs down too fast. A balance between tension, density, profile is essential. And we haven't discussed weight yet, another important consideration especially as it relates to different parts of the scale. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Friday, March 15, 2013 2:46 PM To: David Love Subject: Voicing: RE:lacquer voicing Thanks for those detailed posts, David. Very interesting and insightful. However, they are a little tangential to the topic, which is how you should proceed in voicing a lacquered hammer. It is all very well to explain why you shouldn't choose a hammer that needs to be lacquered, but the practical fact is that as piano technicians, particularly as technicians who service concert venues of one sort or other, the hammers are often to almost always lacquered hammers. So we need to know what to do, what works. The fact of the matter is that lacquered hammers can be made more than just acceptable, as evidenced by the broad range of people who accept them - and I am among them as a pianist. I can't honestly say I prefer one type of hammer over the other in some absolute way. I do prefer the wider range of tone color in a well chosen, well-prepped non-lacquered tensioned hammer, but that is not an absolute preference. There are plenty of the same non-lacquered hammer that I don't prefer, depending usually on prep (and things get so complex so fast, with so many other variables, that one can't really make any blanket statements that are meaningful). In any case, what I really want to get at here is a discussion of what procedures seem to be best in the original set up of a set of lacquered hammers and in their upkeep over time. That is something I deal with on a weekly basis, it's a big part of my job. There are thousands of Steinways with lacquered hammers out there that need care, so we need to know how to give it. BTW, I agree with your last statement: "Put the hammer on there that needs the least amount of hammer abuse. And make no mistake, it is all abuse." - although with the caveat that I don't know that any hammer sounds better "out of the box" than it does when opened up a little, so maybe I would temper that statement to say that the initial opening up is, if well executed, not in fact "abuse" but a necessary procedure to adjust the felt after pressing for optimum tone gradient. And I would add that, with lacquered hammers, the amount of lacquer should be "just enough." Too much lacquer is another kind of hammer abuse. When it is "just enough," the hammer can, IMO, have resilience and behave pretty analogously to the tensioned hammer, again with minimum needle insertions done with consistency and care. That, at any rate, is what my experience has seemed to teach me. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

David,
While I think the general principles you set out are sound, I think there is a danger in labeling and categorizing too much. Isn't the range of hammer styles more of a continuum? The lacquer hammer, over-lacquered, has the characteristics you describe, but in my experience a hammer lacquered "just right" continues to have characteristics you ascribe to the "tensioned" hammer, continues to have resilience, and can have a long useful life.

A case in point is our newest D in the UNM recital hall, 9 years old, original hammers. I have done minimal work to these hammers, never added a drop of lacquer (very nicely set up when we got it). For the first couple years, all I did was crown voicing, shallow, thin needle. Then for a few years single needle close to the crown, somewhat deep. Then, more recently, a full shoulder needling, maybe 7 - 8 deep (10 mm) insertions of three needles each shoulder of every hammer - which, somewhat to my surprise, "opened up" the sound in a way similar to the analogous treatment of a Renner or Abel hammer. I suspect I will retire before these hammers are replaced (5 more years in all likelihood). So here is an example of longevity and quality: everyone likes this piano. Plenty of power, wide dynamic range, wide range of color and control.

I have worked with over-lacquered hammers that have deteriorated rapidly in tone, and needed far more maintenance work, so I do agree with your assessment of some of the down sides. But at the same time I am intrigued by the fact that there seems to be a "special lacquer sound" that can be quite appealing, and is particularly so when dealing with a large concert hall instrument that has to project over an orchestra. A penetrating sound with brilliance, but it doesn't have to be harsh and ugly if you know what you are doing. Despite the fact that this procedure of lacquering is probably the "result of a mistake" - an evolution of technicians dealing with too heavy a hammer without adequate density of felt at the crown - the results are not a disaster by any means. I generally prefer another approach for smaller halls, and definitely for small rooms and houses, but that is another end of the spectrum.

Something to bear in mind is that the Hamburg hammer, trying to do the same thing as the NY hammer but without lacquer, is extraordinarily dense and requires an enormous amount of shoulder work, or so I understand. (I've worked with similar hammers from Renner, but not with that specific, "official Steinway" hammer). Can a hammer be made to perform satisfactorily in this way (ie, concerto instrument) "out of the box?" We have two examples, one that needs hardener, the other that needs a lot of shoulder work. Is it actually possible to manufacture a hammer that has the power and bite but doesn't need either of those components? Personally I doubt it. I think probably it is possible to avoid the degree of shoulder work done by Hamburg (50-75 insertions per shoulder I am told), but I have yet to see the hammer that doesn't really need 7 - 8 insertions per shoulder. 

Of course, I recognize that we are isolating the hammer here, and the whole design of the piano needs to be taken into account - but we aren't the ones designing (most of us), and for practical purposes we need to take that design (Steinway D in particular) as a given in our everyday work. For most of us, the hammer and how we treat it is the biggest variable we have to work with.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-15-2013 19:29
From: David Love
Subject: lacquer voicing

It was slightly tangential as I think your procedures did a good job of covering how best to work with a lacquered hammer. I agree with many of your suggestions although how far the hammer should shift remains a point of debate, I prefer to have the pedal be able to shift off the left string if needed. Let the pianist decide and control that but give them the option. If they don't prefer that then reset it. It's just the turn of a stop screw. The exception to that would be when overshifting drives the hammer into the adjacent note. Then you are limited. Otherwise I basically agree with what you outlined. It is not tangential in the sense that people are choosing to replace hammers with those that need to be lacquered. There is reason to consider avoiding the problems associated with lacquer both in the short and long term.

If we are skilled piano technicians we can make anything sound good. That's our job and we are faced with that dilemma all the time. We may have to rely on our arsenal of extreme voicing procedures and there's a virtual cottage industry out there with all kinds of acceptable methods now being taught at conventions such as pliers, dremel tools, snuggle, alcohol, shellac, steam and, yes, lacquer. There are also short cuts designed to side step the foundational procedures such as the recent "angel shot" craze. That's a different thing, however, from discussing what makes a hammer function properly or what our target should be. We get used to things, for better or for worse, and come to accept them as the norm, or even the goal. The lacquer procedure itself arose in conjunction with a failed hammer, it wasn't a preplanned design. We shouldn't forget that.

I wasn't suggesting that hammers sound better out of the box. Most of the hammers we get today don't sound better out of the box. They almost all need opening up (or a careful manipulation of the density gradient) to a greater or lesser degree--mostly greater. That's the current state of hammer making for some reason. I consider it a bad habit that we can't seem to break. The problem lies to some degree with certain felt making practices. But most of the blame falls on the hammer makers. They are too often simply doing things that they shouldn't. One thing the quality felt makers will tell you: better felt suffers more under bad procedures than poorer felt. It's not enough that the felt is of high quality to start with. It's easy to ruing a good piece of felt.

Those that don’t need a lot of opening up are the ones we are talking about, the ones that need an increase in density, a closing up, as it were, thus lacquer. There are some exceptions but unless careful profiling is done with those hammers (preferably before they reach the press) they will have the opposite problem, inadequate resistance to compression and we end up adding material to stiffen or densify (is that a word?) the felt. The density/profile (thickness of the felt over the wood molding) relationship is very critical and no one is really talking about it, well, except me. Lower density felts (or lower density pressings) need lower profiles, period. Higher density felts or felts with inadequate tension (or both as is often the case) are usually served better by higher profiles.

There is never a reason for a high profile/low density relationship and never a reason for a low profile/high density relationship.

In the first case you are destined to add stiffness and density chemically because there is no other way to get the non-linear spring effect. Of course you can file them but that has other ramifications, as I outlined previously. If the hammers are already hung then the kind of filing often required will screw up your regulation, bore distance and create other problems. The more "stuff" you add the more problems you have with unwanted noise, lost resilience, poor wear and development--the classic NY D hammer.

In the second case, you don't have enough material to open up. The amount of needling needed in a low profile/high density hammer will necessarily destroy tension and turn the hammer into a density gradient driven hammer except that the low profile gives you an inadequate amount of material for the kind of progressive dynamic curve that you want and also impacts the stability--it packs down too fast. A balance between tension, density, profile is essential.

And we haven't discussed weight yet, another important consideration especially as it relates to different parts of the scale.



David Love
www.davidlovepianos.com

Fred: I suppose there is a danger in labeling or categorizing but let's not let that danger make us too complacent either. I don't think it's quite a continuum. I think hammers exist on either side of the continuum without much in the middle. As I said, it is our job to develop the skills to deal with anything and overall we do a pretty good job of that. There are some very creative solutions to problems that we (technicians) have come up with and to our credit. That we have allowed that creativity to influence our acceptance of products (and procedures) that are less than optimal when it comes to what I consider delivering or maintaining a quality hammer is unfortunate. Am I soap boxing a bit? Well yes, I admit it. But I'm getting just old enough to stop pulling punches for the sake of politicking. I have had very few experiences with hammers lacquered enough to create the kind of power necessary on a D that didn't sooner than later develop problems associated with lacquer: noise, a difficult to control dynamic continuum, progressive hardening over time, strike point deterioration from the requirements of crown needling, lack of flexibility and resilience. If it does happen, it is the exception and not the rule. I don't think I'm the only one who holds that opinion among the very highly skilled and reputable concert technicians many of whom are eschewing the NYD hammer when given a chance. Also, a concert piano is a bit different, it gets constant attention, every performance virtually. That is not a good measure of what we should be expecting on a day to day basis. I agree that the Hamburg hammer (which I have worked with on many occasions) requires a lot of work to "open up". It's very dense and heavy, what there is of the spring is very tightly compressed and there's little room for movement within the hammer without a lot of work, more than is desirable for a number of reasons, again, in my opinion. (BTW the same is also true of Boesendorfer hammers and Bechstein hammers from my experience. I have not worked with a Fazioli hammer from scratch so I can't comment there.) It (the Hamburg Steinway) is also a very heavy hammer, too heavy in the treble section (above note 55 or so where weight begins to be a detriment) and is not what I would consider the gold standard. Honestly, I'm not sure what is. The amount of needling required to open them up basically destroys whatever tension there might have been there to begin with. Needling, I think we can agree, does result in loss of tension. There is a finite amount in any hammer, once it's gone, it's gone for good. Loss of tension means less stability, in my experience. Hammers that come out of the box with no tension (and there are many) get bright, harsh and loud very quickly. Hammers with lots of tension (superball like) don't, at least not as quickly. Felt under tension is more resilient, sounds different, reacts different, exhibits different qualities of stability. There is a cost for a hammer that requires that much opening up. The cost is tension. If one is of the opinion that tension doesn't matter, well, then it doesn't matter. I don't happen to think that. We don't really know the reason that manufacturers demand products at this end of the continuum, or if they even do. We might note that Yamaha (and Kawai for that matter) have backed off considerably on their hammer densities over the past decade or more and to their credit, in my view. However, what may drive the call for the upper end of the density continuum may be an avoidance response. Manufacturers may fear lack of power more than too much power. It is, after all, somewhat easier to bring something down than it is to bring something up. Better, perhaps, to start with too much power than not enough forcing you to resort to chemicals with their own set of problems. But how much above do we need to target (if that's our philosophy) and that does beg the question. Can a hammer be made such that it produces close to what we want out of the box? The impedance characteristics of any given belly no doubt complicate matters and that is yet another discussion worth having but it is still a legitimate question since they don't seem to exist. The issue is not a "perfect" match out of the box, but a closer one. But I don't think it's because they can't exist. I think there are several reasons that they don't exist, which I don't want to get into at this point, but some of it seems to be cost driven, some of it is just habit, and some it may be a misdirected concern with visual esthetics and associated goals that are contrary to functional requirements. It is something that I'm working on at present. To better define what I want in a hammer in terms of performance and the qualities and dimensions that must be satisfied to get there. Preliminary experiments are promising and I'll get into it more when I'm ready, but not now. So my answer is that I don't think it's impossible. I do think we have settled too much for what is offered rather than learning what we want and making greater demands along those lines. If we don't do that, we have no one to blame but ourselves. I will certainly grant you that there is an element of personal taste in all of this. But much like the problems associated with cultural relativism, I think we can begin to identify underlying qualities that transcend personal taste and opinion. At least, I think we should try. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Saturday, March 16, 2013 9:34 AM To: David Love Subject: Voicing: RE:lacquer voicing David, While I think the general principles you set out are sound, I think there is a danger in labeling and categorizing too much. Isn't the range of hammer styles more of a continuum? The lacquer hammer, over-lacquered, has the characteristics you describe, but in my experience a hammer lacquered "just right" continues to have characteristics you ascribe to the "tensioned" hammer, continues to have resilience, and can have a long useful life. A case in point is our newest D in the UNM recital hall, 9 years old, original hammers. I have done minimal work to these hammers, never added a drop of lacquer (very nicely set up when we got it). For the first couple years, all I did was crown voicing, shallow, thin needle. Then for a few years single needle close to the crown, somewhat deep. Then, more recently, a full shoulder needling, maybe 7 - 8 deep (10 mm) insertions of three needles each shoulder of every hammer - which, somewhat to my surprise, "opened up" the sound in a way similar to the analogous treatment of a Renner or Abel hammer. I suspect I will retire before these hammers are replaced (5 more years in all likelihood). So here is an example of longevity and quality: everyone likes this piano. Plenty of power, wide dynamic range, wide range of color and control. I have worked with over-lacquered hammers that have deteriorated rapidly in tone, and needed far more maintenance work, so I do agree with your assessment of some of the down sides. But at the same time I am intrigued by the fact that there seems to be a "special lacquer sound" that can be quite appealing, and is particularly so when dealing with a large concert hall instrument that has to project over an orchestra. A penetrating sound with brilliance, but it doesn't have to be harsh and ugly if you know what you are doing. Despite the fact that this procedure of lacquering is probably the "result of a mistake" - an evolution of technicians dealing with too heavy a hammer without adequate density of felt at the crown - the results are not a disaster by any means. I generally prefer another approach for smaller halls, and definitely for small rooms and houses, but that is another end of the spectrum. Something to bear in mind is that the Hamburg hammer, trying to do the same thing as the NY hammer but without lacquer, is extraordinarily dense and requires an enormous amount of shoulder work, or so I understand. (I've worked with similar hammers from Renner, but not with that specific, "official Steinway" hammer). Can a hammer be made to perform satisfactorily in this way (ie, concerto instrument) "out of the box?" We have two examples, one that needs hardener, the other that needs a lot of shoulder work. Is it actually possible to manufacture a hammer that has the power and bite but doesn't need either of those components? Personally I doubt it. I think probably it is possible to avoid the degree of shoulder work done by Hamburg (50-75 insertions per shoulder I am told), but I have yet to see the hammer that doesn't really need 7 - 8 insertions per shoulder. Of course, I recognize that we are isolating the hammer here, and the whole design of the piano needs to be taken into account - but we aren't the ones designing (most of us), and for practical purposes we need to take that design (Steinway D in particular) as a given in our everyday work. For most of us, the hammer and how we treat it is the biggest variable we have to work with. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

I'd like to address this statement by David Love:
"I have had very few experiences with hammers lacquered enough to create the kind of power necessary on a D that didn't sooner than later develop problems associated with lacquer: noise, a difficult to control dynamic continuum, progressive hardening over time, strike point deterioration from the requirements of crown needling, lack of flexibility and resilience. If it does happen, it is the exception and not the rule. I don't think I'm the only one who holds that opinion among the very highly skilled and reputable concert technicians many of whom are eschewing the NYD hammer when given a chance."

I don't dispute this as a common experience. I do, however, dispute the notion that it needs to be the rule. Take crown voicing, for instance. If you use the "official Steinway tool" for the purpose, yes, you will destroy the crown in fairly short order. However, if you use fine needles, spaced appropriately, to do your crown work, the hammers can last nicely with far less deterioration, and can really be quite similar in longevity and maintenance needs to any other hammer used - at least any other hammer that produces the power and brilliance needed in the concert circumstance.

Similarly with the shoulders. If you use the "official Steinway procedure" of saturating all the felt of the hammers, usually at least twice, then you will have the body of a hammer that is quite stiff, that inhibits the possibility of range of color, and in which tone color will deteriorate and become harsh rather rapidly. If, OTOH, you lacquer only as much as needed where needed, and avoid saturating the shoulders in favor of building up the core, the shoulders are similar to the opened up shoulders of a denser hammer, the range of color will be greater, and the tone will not deteriorate and become harsh so rapidly. 

I write from the experience of being the only one doing maintenance on a few concert instruments over many, many years - two of them heavy use, others not so heavy. I do not need to tweak the voicing weekly. Every 2 - 3 months is really sufficient for a pretty high standard (it could, of course, be improved), and we are talking instruments that often have as many as 6 - 10 concerts a week with associated rehearsals. This is not soapbox philosophizing, it is simple day to day experience, built from an examination and either adaptation, rejection or modification of techniques learned from others, together with a bit of reasoning and invention. But mostly experience: What works? What doesn't?

I assume other people have experimented and might have a variety of thoughts along these lines - but perhaps I am wrong. I know there are a lot of us maintaining these instruments with these hammers, many quite successfully for many years. 


-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-16-2013 18:56
From: David Love
Subject: lacquer voicing

Fred:

I suppose there is a danger in labeling or categorizing but let's not let that danger make us too complacent either. I don't think it's quite a continuum. I think hammers exist on either side of the continuum without much in the middle. As I said, it is our job to develop the skills to deal with anything and overall we do a pretty good job of that. There are some very creative solutions to problems that we (technicians) have come up with and to our credit. That we have allowed that creativity to influence our acceptance of products (and procedures) that are less than optimal when it comes to what I consider delivering or maintaining a quality hammer is unfortunate. Am I soap boxing a bit? Well yes, I admit it. But I'm getting just old enough to stop pulling punches for the sake of politicking.

I have had very few experiences with hammers lacquered enough to create the kind of power necessary on a D that didn't sooner than later develop problems associated with lacquer: noise, a difficult to control dynamic continuum, progressive hardening over time, strike point deterioration from the requirements of crown needling, lack of flexibility and resilience. If it does happen, it is the exception and not the rule. I don't think I'm the only one who holds that opinion among the very highly skilled and reputable concert technicians many of whom are eschewing the NYD hammer when given a chance. Also, a concert piano is a bit different, it gets constant attention, every performance virtually. That is not a good measure of what we should be expecting on a day to day basis.

I agree that the Hamburg hammer (which I have worked with on many occasions) requires a lot of work to "open up". It's very dense and heavy, what there is of the spring is very tightly compressed and there's little room for movement within the hammer without a lot of work, more than is desirable for a number of reasons, again, in my opinion. (BTW the same is also true of Boesendorfer hammers and Bechstein hammers from my experience. I have not worked with a Fazioli hammer from scratch so I can't comment there.) It (the Hamburg Steinway) is also a very heavy hammer, too heavy in the treble section (above note 55 or so where weight begins to be a detriment) and is not what I would consider the gold standard. Honestly, I'm not sure what is. The amount of needling required to open them up basically destroys whatever tension there might have been there to begin with. Needling, I think we can agree, does result in loss of tension. There is a finite amount in any hammer, once it's gone, it's gone for good. Loss of tension means less stability, in my experience. Hammers that come out of the box with no tension (and there are many) get bright, harsh and loud very quickly. Hammers with lots of tension (superball like) don't, at least not as quickly. Felt under tension is more resilient, sounds different, reacts different, exhibits different qualities of stability. There is a cost for a hammer that requires that much opening up. The cost is tension. If one is of the opinion that tension doesn't matter, well, then it doesn't matter. I don't happen to think that.

We don't really know the reason that manufacturers demand products at this end of the continuum, or if they even do. We might note that Yamaha (and Kawai for that matter) have backed off considerably on their hammer densities over the past decade or more and to their credit, in my view. However, what may drive the call for the upper end of the density continuum may be an avoidance response. Manufacturers may fear lack of power more than too much power. It is, after all, somewhat easier to bring something down than it is to bring something up. Better, perhaps, to start with too much power than not enough forcing you to resort to chemicals with their own set of problems. But how much above do we need to target (if that's our philosophy) and that does beg the question.

Can a hammer be made such that it produces close to what we want out of the box? The impedance characteristics of any given belly no doubt complicate matters and that is yet another discussion worth having but it is still a legitimate question since they don't seem to exist. The issue is not a "perfect" match out of the box, but a closer one. But I don't think it's because they can't exist. I think there are several reasons that they don't exist, which I don't want to get into at this point, but some of it seems to be cost driven, some of it is just habit, and some it may be a misdirected concern with visual esthetics and associated goals that are contrary to functional requirements.

It is something that I'm working on at present. To better define what I want in a hammer in terms of performance and the qualities and dimensions that must be satisfied to get there. Preliminary experiments are promising and I'll get into it more when I'm ready, but not now. So my answer is that I don't think it's impossible. I do think we have settled too much for what is offered rather than learning what we want and making greater demands along those lines. If we don't do that, we have no one to blame but ourselves.

I will certainly grant you that there is an element of personal taste in all of this. But much like the problems associated with cultural relativism, I think we can begin to identify underlying qualities that transcend personal taste and opinion. At least, I think we should try.

David Love
www.davidlovepianos.com

Fred: I failed to mention that though I agree with you that opening up the hammer is constructive in terms of tone requirements, I still contend that it is a destructive process to the hammer. We seem to agree that the hammer is best which requires the least. That suggest that it comes out of the press performing as close to what we want as possible and that is in all dimensions. The less we have to do to it the better in terms of maintaining tension (especially), and cohesiveness structurally. The question of can we really expect a hammer to come out performing in the manner we need is a valid one. Is the pressing process consistent with producing what we need in terms of performance? Having worked with one hammer maker in particular to achieve that with very specific goals in mind, I would say yes, it is achievable. Without a doubt. David Love www.davidlovepianos.com

Greetings, Weikert felt,Ronsen hammers. They have addressed this question quite well. Great range and power, right out of the box. Very predictable results with the slightest needling. I am putting them in practice room pianos with WNG parts and the results are what I have been looking for for a long time. Regards Ed Foote RPT On Mar 16, 2013, at 5:58 PM, David Love wrote: > > Fred: > > I suppose there is a danger in labeling or categorizing but let's not let > that danger make us too complacent either. I don't think it's quite a > continuum. I think hammers exist on either side of the continuum without > much in the middle. As I said, it is our job to develop the skills to deal > with anything and overall we do a pretty good job of that. There are some> very creative solutions to problems that we (technicians) have come up with > and to our credit. That we have allowed that creativity to influence our > acceptance of products (and procedures) that are less than optimal when it> comes to what I consider delivering or maintaining a quality hammer is > unfortunate. Am I soap boxing a bit? Well yes, I admit it. But I'm > getting just old enough to stop pulling punches for the sake of politicking. > > > I have had very few experiences with hammers lacquered enough to create the > kind of power necessary on a D that didn't sooner than later develop > problems associated with lacquer: noise, a difficult to control dynamic > continuum, progressive hardening over time, strike point deterioration from > the requirements of crown needling, lack of flexibility and resilience. If > it does happen, it is the exception and not the rule. I don't think I'm the > only one who holds that opinion among the very highly skilled and reputable > concert technicians many of whom are eschewing the NYD hammer when given a> chance. Also, a concert piano is a bit different, it gets constant > attention, every performance virtually. That is not a good measure of what > we should be expecting on a day to day basis. > > I agree that the Hamburg hammer (which I have worked with on many occasions) > requires a lot of work to "open up". It's very dense and heavy, what there > is of the spring is very tightly compressed and there's little room for > movement within the hammer without a lot of work, more than is desirable for > a number of reasons, again, in my opinion. (BTW the same is also true of > Boesendorfer hammers and Bechstein hammers from my experience. I have not> worked with a Fazioli hammer from scratch so I can't comment there.) It > (the Hamburg Steinway) is also a very heavy hammer, too heavy in the treble > section (above note 55 or so where weight begins to be a detriment) and is> not what I would consider the gold standard. Honestly, I'm not sure what > is. The amount of needling required to open them up basically destroys > whatever tension there might have been there to begin with. Needling, I > think we can agree, does result in loss of tension. There is a finite > amount in any hammer, once it's gone, it's gone for good. Loss of tension> means less stability, in my experience. Hammers that come out of the box > with no tension (and there are many) get bright, harsh and loud very > quickly. Hammers with lots of tension (superball like) don't, at least not > as quickly. Felt under tension is more resilient, sounds different, reacts > different, exhibits different qualities of stability. There is a cost for a > hammer that requires that much opening up. The cost is tension. If one is > of the opinion that tension doesn't matter, well, then it doesn't matter. I > don't happen to think that. > > We don't really know the reason that manufacturers demand products at this> end of the continuum, or if they even do. We might note that Yamaha (and > Kawai for that matter) have backed off considerably on their hammer > densities over the past decade or more and to their credit, in my view. > However, what may drive the call for the upper end of the density continuum > may be an avoidance response. Manufacturers may fear lack of power more > than too much power. It is, after all, somewhat easier to bring something> down than it is to bring something up. Better, perhaps, to start with too> much power than not enough forcing you to resort to chemicals with their own > set of problems. But how much above do we need to target (if that's our > philosophy) and that does beg the question. > > Can a hammer be made such that it produces close to what we want out of the > box? The impedance characteristics of any given belly no doubt complicate> matters and that is yet another discussion worth having but it is still a > legitimate question since they don't seem to exist. The issue is not a > "perfect" match out of the box, but a closer one. But I don't think it's > because they can't exist. I think there are several reasons that they don't > exist, which I don't want to get into at this point, but some of it seems to > be cost driven, some of it is just habit, and some it may be a misdirected> concern with visual esthetics and associated goals that are contrary to > functional requirements. > > It is something that I'm working on at present. To better define what I want > in a hammer in terms of performance and the qualities and dimensions that > must be satisfied to get there. Preliminary experiments are promising and> I'll get into it more when I'm ready, but not now. So my answer is that I> don't think it's impossible. I do think we have settled too much for what> is offered rather than learning what we want and making greater demands > along those lines. If we don't do that, we have no one to blame but > ourselves. > > I will certainly grant you that there is an element of personal taste in all > of this. But much like the problems associated with cultural relativism, I> think we can begin to identify underlying qualities that transcend personal > taste and opinion. At least, I think we should try. > >

Are you saying that the power that you want out of the box on a practice room piano is the same as what you want in a concert piano? I agree, btw, that it is a great product, but there are some dimensional targets that I think are critical. More on that later. David Love www.davidlovepianos.com
Original Message----- From: Edward Foote [mailto:noreply@egroups.ptg.org] Sent: Saturday, March 16, 2013 4:23 PM To: David Love Subject: Voicing : lacquer voicing Greetings, Weikert felt,Ronsen hammers. They have addressed this question quite well. Great range and power, right out of the box. Very predictable results with the slightest needling. I am putting them in practice room pianos with WNG parts and the results are what I have been looking for for a long time. Regards Ed Foote RPT On Mar 16, 2013, at 5:58 PM, David Love wrote: > > Fred: > > I suppose there is a danger in labeling or categorizing but let's not > let that danger make us too complacent either. I don't think it's > quite a continuum. I think hammers exist on either side of the > continuum without much in the middle. As I said, it is our job to > develop the skills to deal with anything and overall we do a pretty > good job of that. There are some> very creative solutions to problems that we (technicians) have come up with > and to our credit. That we have allowed that creativity to influence > our acceptance of products (and procedures) that are less than optimal > when it> comes to what I consider delivering or maintaining a quality hammer is > unfortunate. Am I soap boxing a bit? Well yes, I admit it. But I'm > getting just old enough to stop pulling punches for the sake of politicking. > > > I have had very few experiences with hammers lacquered enough to > create the kind of power necessary on a D that didn't sooner than > later develop problems associated with lacquer: noise, a difficult to > control dynamic continuum, progressive hardening over time, strike > point deterioration from the requirements of crown needling, lack of > flexibility and resilience. If it does happen, it is the exception > and not the rule. I don't think I'm the only one who holds that > opinion among the very highly skilled and reputable concert > technicians many of whom are eschewing the NYD hammer when given a> chance. Also, a concert piano is a bit different, it gets constant > attention, every performance virtually. That is not a good measure of > what we should be expecting on a day to day basis. > > I agree that the Hamburg hammer (which I have worked with on many > occasions) requires a lot of work to "open up". It's very dense and > heavy, what there is of the spring is very tightly compressed and > there's little room for movement within the hammer without a lot of > work, more than is desirable for a number of reasons, again, in my > opinion. (BTW the same is also true of Boesendorfer hammers and > Bechstein hammers from my experience. I have not> worked with a Fazioli hammer from scratch so I can't comment there.) It > (the Hamburg Steinway) is also a very heavy hammer, too heavy in the > treble section (above note 55 or so where weight begins to be a > detriment) and is> not what I would consider the gold standard. Honestly, I'm not sure what > is. The amount of needling required to open them up basically > destroys whatever tension there might have been there to begin with. > Needling, I think we can agree, does result in loss of tension. There > is a finite amount in any hammer, once it's gone, it's gone for good. > Loss of tension> means less stability, in my experience. Hammers that come out of the box > with no tension (and there are many) get bright, harsh and loud very > quickly. Hammers with lots of tension (superball like) don't, at > least not as quickly. Felt under tension is more resilient, sounds > different, reacts different, exhibits different qualities of > stability. There is a cost for a hammer that requires that much > opening up. The cost is tension. If one is of the opinion that > tension doesn't matter, well, then it doesn't matter. I don't happen to think that. > > We don't really know the reason that manufacturers demand products at > this> end of the continuum, or if they even do. We might note that Yamaha (and > Kawai for that matter) have backed off considerably on their hammer > densities over the past decade or more and to their credit, in my > view. > However, what may drive the call for the upper end of the density continuum > may be an avoidance response. Manufacturers may fear lack of power > more than too much power. It is, after all, somewhat easier to bring > something> down than it is to bring something up. Better, perhaps, to start with too> much power than not enough forcing you to resort to chemicals with their own > set of problems. But how much above do we need to target (if that's > our > philosophy) and that does beg the question. > > Can a hammer be made such that it produces close to what we want out > of the box? The impedance characteristics of any given belly no doubt > complicate> matters and that is yet another discussion worth having but it is still a > legitimate question since they don't seem to exist. The issue is not > a "perfect" match out of the box, but a closer one. But I don't think > it's because they can't exist. I think there are several reasons that > they don't exist, which I don't want to get into at this point, but > some of it seems to be cost driven, some of it is just habit, and some > it may be a misdirected> concern with visual esthetics and associated goals that are contrary to > functional requirements. > > It is something that I'm working on at present. To better define what > I want > in a hammer in terms of performance and the qualities and dimensions > that must be satisfied to get there. Preliminary experiments are > promising and> I'll get into it more when I'm ready, but not now. So my answer is that I> don't think it's impossible. I do think we have settled too much for what> is offered rather than learning what we want and making greater demands > along those lines. If we don't do that, we have no one to blame but > ourselves. > > I will certainly grant you that there is an element of personal taste > in all of this. But much like the problems associated with cultural > relativism, I> think we can begin to identify underlying qualities that transcend personal > taste and opinion. At least, I think we should try. > >

I would draw your attention to the subject line: lacquer voicing. I was hoping to have a discussion on techniques that work (or don't work) in the treatment of hammers that are lacquered, specifically Steinways, and with an emphasis on concert instruments.

Yes, there are alternative hammers out there, and that is a good discussion to have as well, but as piano technicians we need to know how to work on lacquered hammers, and my hope is that we might have a conversation that does not veer instantly into such tangents as what hammers are preferable to those that need lacquer, why use of lacquer is either evil or a mistake, etc., etc., but at least tries to stick to what to do when setting up and maintaining lacquered hammers, and why.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-16-2013 19:15
From: Edward Foote
Subject: lacquer voicing

Greetings,

Weikert felt,Ronsen hammers. They have addressed this question quite well. Great range and power, right out of the box. Very predictable results with the slightest needling. I am putting them in practice room pianos with WNG parts and the results are what I have been looking for for a long time.
Regards
Ed Foote RPT

I've worked quite a bit with Steinway hammers and have enjoyed the creative challenges in voicing them, however, would you agree, especially in an institutional setting, that lacquered hammers require more maintenance than non lacquered? The more one plays on lacquered hammers the more the deeper lacquered layers of felt comes up to the surface thereby having to constantly voice them. It seems, depending on the hammer, that is not so much the case with heat compressed hammers. Your thoughts? ------------------------------------------- Andrew Saderman Forest Hills NY 718-263-6508 -------------------------------------------
Original Message: Sent: 03-16-2013 23:47 From: Fred Sturm Subject: lacquer voicing I would draw your attention to the subject line: lacquer voicing. I was hoping to have a discussion on techniques that work (or don't work) in the treatment of hammers that are lacquered, specifically Steinways, and with an emphasis on concert instruments. Yes, there are alternative hammers out there, and that is a good discussion to have as well, but as piano technicians we need to know how to work on lacquered hammers, and my hope is that we might have a conversation that does not veer instantly into such tangents as what hammers are preferable to those that need lacquer, why use of lacquer is either evil or a mistake, etc., etc., but at least tries to stick to what to do when setting up and maintaining lacquered hammers, and why. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------
Original Message: Sent: 03-16-2013 19:15 From: Edward Foote Subject: lacquer voicing Greetings, Weikert felt,Ronsen hammers. They have addressed this question quite well. Great range and power, right out of the box. Very predictable results with the slightest needling. I am putting them in practice room pianos with WNG parts and the results are what I have been looking for for a long time. Regards Ed Foote RPT

With respect to longevity of voicing in lacquered hammers, I think two things are key, beyond the initial set up (without excess lacquer, preferably without the entire hammer saturated).

First is maintenance crown voicing, which should be done with small enough diameter needles. Large needles are very destructive, and particularly to the felt right at the crown. I use #12 needles, the smallest readily available size (quilting needles), spaced 1.0 - 1.5 mm apart, extending 2 - 3 mm. I use them right in the string grooves when those have developed a bit and when the piano has developed an edge to the tone. The first time it will be one insertion perpendicular to the hammer, one per every string groove (quite fast, 20 minutes or less should do the whole piano). This will, in fact, reverse some of the packing of felt, making the grooves less apparent visually. And the tonal result is obvious, immediate, but subtle: it tends to be enough without the danger of going too far.

After a filing or two, it will usually be necessary to expand that procedure a bit, and, using the same tool, go at each groove from 1 and 11 o'clock, a bit of cross needling (though it is quite shallow). This kind of maintenance needling is quite stable as such things go, and it is minimally destructive to the fibers. (I'm not mentioning una corda voicing here, but that tends to be more stable for me because I have used bigger diameter, slightly longer needles initially, and because there is less packing from playing. But a similar regimen of maintenance voicing keeps that in good condition as well).

When this isn't sufficient, it is usually because you have worn down to the point that there is a broader profile of relatively heavily lacquered felt. At this point, standard upper crown needling of the sort one does with dense, unlacquered hammers comes into play. Insertions that come up to a point, that is to say that you work up the upper shoulder, and as you approach the center of the crown, you angle outwards, leaving the classic triangle point untouched (it is only touched by the small diameter needles, and only fairly shallowly). I generally use a 3 needle tool, #6 or so needles, 10 mm, and insert them fully (tapering this in the top 2 octaves - possibly only using smaller needles in the top octave). If the the 3 needle tool won't insert readily, there is too much lacquer. In which case you could use one needle, but you would probably be better served soaking some of the lacquer out in my experience. When there is too much lacquer, these maintenance procedures don't work nearly as well.

With this kind of consistent procedure (on hammers that have not been over-lacquered), I have found that both concert pianos and other heavy use pianos can be kept at a high level without hammer replacement for several years.

Interestingly I have 2 Bs in a piano faculty studio, one 20 year old lacquered, the other 5 - 6 year old Abels (relatively dense). The lacquered piano is used more (students play on that one). And it is more stable and has required less maintenance time - not a night and day difference by any means, but definitely more work for the Abels. I suspect that one more thorough shoulder needling will finally bring that one to a pretty stable state. 

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-17-2013 07:20
From: Andrew Saderman
Subject: lacquer voicing



I've worked quite a bit with Steinway hammers and have enjoyed the creative challenges in voicing them, however, would you agree, especially in an
institutional setting, that lacquered hammers require more maintenance than non lacquered? The more one plays on lacquered hammers the more the
deeper lacquered layers of felt comes up to the surface thereby having to constantly voice them. It seems, depending on the hammer, that is not so much the case with heat compressed hammers. Your thoughts?
-------------------------------------------
Andrew Saderman
Forest Hills NY
718-263-6508
-------------------------------------------

A little addendum having to do with working with hammers that have been saturated. While I don't believe the saturation is necessary - the shoulders of Steinway hammers seem to be "just about right" without adding lacquer - saturation doesn't necessarily hurt. One thing it can do is to lead to less longevity of the voicing, the hammers sounding harsher and having less tonal gradient. And the solution that works for me is quite simple: standard shoulder needling, deep, three needle tool, 10 mm long, about 7 - 8 insertions per shoulder, classic pattern. This opens up the tone and creates a larger spectrum, in my experience, and avoids the "becoming harsh" syndrome.

The caveat, though, is that if the shoulders have been over-lacquered, this doesn't work. One "standard NY Steinway" saturation is fine (4% solids or so). Two is still workable. Three or more, and the needles don't have the same effect, in fact have next to no effect. So in that case, I would wash lacquer out of the hammers.

Over the years, I have come to think of the lacquer hammer as simply another approach to achieve the same aim: 
A solid core under the strike point (classic triangle profile)
resilient shoulders, providing enough tension to support the core while also providing a "springiness" that enhances the tonal gradient.

I agree wholeheartedly with David Love that you get there by stiffening the core, and that stiffening the shoulders without addressing the core is counterproductive (though that is what Steinway was teaching us back in the 80s, and the idea persists). For a concert instrument, especially a concerto instrument, that core needs to be pretty darned hard, whether it is achieved by compression or by stiffening the fibers. I believe that as long as we are careful in the amount and placement of lacquer, and in the treatment of the lacquered felt, we can achieve essentially the same results as with a hammer that got a denser core by pressing. 

I'm not sure I believe that it is possible for a hammer to be made so that it has the necessary bite for this application without needing either considerable shoulder needling or considerable core hardening. Lower the expectation of "bite and brilliance" and maybe it will be possible. The concert instrument is a special case, and it is a real shame that it tends to drive the design and treatment of smaller instruments, which are usually better off with a different kind of set up.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-17-2013 23:55
From: Fred Sturm
Subject: lacquer voicing

With respect to longevity of voicing in lacquered hammers, I think two things are key, beyond the initial set up (without excess lacquer, preferably without the entire hammer saturated).

First is maintenance crown voicing, which should be done with small enough diameter needles. Large needles are very destructive, and particularly to the felt right at the crown. I use #12 needles, the smallest readily available size (quilting needles), spaced 1.0 - 1.5 mm apart, extending 2 - 3 mm. I use them right in the string grooves when those have developed a bit and when the piano has developed an edge to the tone. The first time it will be one insertion perpendicular to the hammer, one per every string groove (quite fast, 20 minutes or less should do the whole piano). This will, in fact, reverse some of the packing of felt, making the grooves less apparent visually. And the tonal result is obvious, immediate, but subtle: it tends to be enough without the danger of going too far.

After a filing or two, it will usually be necessary to expand that procedure a bit, and, using the same tool, go at each groove from 1 and 11 o'clock, a bit of cross needling (though it is quite shallow). This kind of maintenance needling is quite stable as such things go, and it is minimally destructive to the fibers. (I'm not mentioning una corda voicing here, but that tends to be more stable for me because I have used bigger diameter, slightly longer needles initially, and because there is less packing from playing. But a similar regimen of maintenance voicing keeps that in good condition as well).

When this isn't sufficient, it is usually because you have worn down to the point that there is a broader profile of relatively heavily lacquered felt. At this point, standard upper crown needling of the sort one does with dense, unlacquered hammers comes into play. Insertions that come up to a point, that is to say that you work up the upper shoulder, and as you approach the center of the crown, you angle outwards, leaving the classic triangle point untouched (it is only touched by the small diameter needles, and only fairly shallowly). I generally use a 3 needle tool, #6 or so needles, 10 mm, and insert them fully (tapering this in the top 2 octaves - possibly only using smaller needles in the top octave). If the the 3 needle tool won't insert readily, there is too much lacquer. In which case you could use one needle, but you would probably be better served soaking some of the lacquer out in my experience. When there is too much lacquer, these maintenance procedures don't work nearly as well.

With this kind of consistent procedure (on hammers that have not been over-lacquered), I have found that both concert pianos and other heavy use pianos can be kept at a high level without hammer replacement for several years.

Interestingly I have 2 Bs in a piano faculty studio, one 20 year old lacquered, the other 5 - 6 year old Abels (relatively dense). The lacquered piano is used more (students play on that one). And it is more stable and has required less maintenance time - not a night and day difference by any means, but definitely more work for the Abels. I suspect that one more thorough shoulder needling will finally bring that one to a pretty stable state. 

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------

There is no end to the expectations of what one perceives as a desired result in any given situation.

One does what one believes is the best course of action in the world in which they live in.

There are no mistakes, only learning.

Keith McGavern, RPT
Shawnee, Oklahoma, USA
tune-repair@allegiance.tv

Original Message:
Sent: 03-18-2013 14:25
From: Fred Sturm
... I'm not sure I believe that it is possible for a hammer to be made so that it has the necessary bite for this application without needing either considerable shoulder needling or considerable core hardening. ...

Hi, all -

This is a terrific discussion, with so much content offered from so much earnest experience. My thanks to David and Fred, in particular, and to Ed and Ben and each of you who have spoken up. And my thanks especially for discussing this complex topic.

You have greatly augmented my arsenal of specifics to try and consider. In my career, concert tuning has been an sporadic duty. The same with dealing with lacquered hammers. But maybe there are more of us in this category than specialists, who are forced in the fray to personally master the challenges. So, first a brief rant (which has already been somewhat addressed by your offerings) and then a couple of questions to the experts. And finally, the useful two-bits I have to offer.

I can understand two good reasons for the adding solids model of hammer preparation, one addressing the need to project to the back of a large or acoustically challenged hall, and the other addressing (but maybe not?) the need to retard wear in the heavily played hammer. My main annoyance with it as the choice of Steinway & Sons, an industry leader and the maker of otherwise mostly (a couple of action item exceptions, topics for other discussions) excellent and exceptional pianos, is that it requires too much skill of the thousands of us technicians that service them to produce consistently excellent tonal results. Too much skill? Look at the old Steinway approach to tone building vs. the new. Look at Fred's approach vs. David's. Just look at the pictures Ben provided: a very neat job, generally, but full of questions for me as to how to get those techniques just right and how to best integrate the different variables into a wholly wonderful sounding piano voice. It's the challenging, expert end of our work, anyway, but solids added are hard to control, assess, and negotiate, i.e., they complicate things before they solve things.

Part of the rant is how long it takes, the early on commitments in the adding that take huge work to recover from if you don't get it quite right, and general difficulty in micro-managing hidden hard spots, only found by prodding soft-enough-already spots. This time/energy complaint, of course, has a serious counterpart in the dense, non-lacquered approach. Anyway, a lot of Steinways in our current era don't sound as good as it seems like they should, IMO. And that may be largely due to technician error, mea culpa. But, well, exactly. I try hard, put in the time, think hard, and try to listen hard (to others and the piano at hand), as due plenty of others do, while producing not-quite-what-we-were-hoping-for results.

And the advantages are mostly for the concert instrument. Fine. A specialty treatment, handled by specialists, for the special situation. But what about the general populous of pianos in the entire rest of the marketplace? End rant.

There are clearly different approaches to lacquering hammers that can have successful results. I imagine those in Fred's care compare favorably to those in David's care and vice versa. Both of your approaches seem to be variations on harden the core, with gradiants of increasingly softer material to the softest on surface. Have you tried the corollary of that, where the tension layer is reinforced, instead of the compression area, so that the center is softer, becoming harder the harder it is played? I suppose making the surface of that reinforced tension layer, the contact layer, sufficiently noise-reduced is the problem, but it might provide a very clear ppp tone and an equally powerful fff. Could a medium mix applied all around, the Stanwood compass needle approach for the surface, and side-needling in the center as needed have merit? Is this sort of the direction Steinway is heading in with lacquering both crown and shoulders?

A variant of that idea is lacquering the under-shoulders, just applying at the staple, limiting the upward wicking, but filling downward to the molding. I've had some success with that technique, both for very hard hammers and for overly soft hammers. In both cases, it seems to enhance their bounce properties, reducing noise content in the one and increasing power in the other. I think of it as being something for the bounce, flexing at the shoulders, to push against. I believe the Steinway through-threaded and twisted-tight staples serve this function, but most of the hammers I use (with the exception of Steinway hammers I am not replacing) either don't have staples or have "t" type staples.

I like the concept of David's approach, but I'm generally dealing with the already lacquered, not the newly-hung to be lacquered. So, thanks, Fred, for some insight into how best to cope with these.

Finally, from what Ben said, Steinway clearly has an emphasis on action prep, regulation, and hammer string mating. I share that sense of emphasis: the preparation behind how the hammer gets to, contacts, and bounces away from its strings is part of voicing the lacquered or unlacquered hammer. The recent string leveling / hammer-to-string fitting discussion covered the contact portion in great detail, but it should be noted that flaws in the foundation behind that fit or in the nature of the fit itself, limit and/or erode what the hammer itself can achieve. To that end, I have tools to help the industry achieve superior prep, regulation, and mating. They are regulation tools, but they are also voicing tools, including the protocols they have engendered. Particularly, the Squaring Platform, with its Hammer Square and Shank Traveler. They help both the skilled and the less skilled to the place where successful voicing can occur. I believe this is particularly important for the lacquered hammer.

Finally, significant time, in my experience, is needed to accomplish the voicing implementations talked about in this discussion. May I ask of those who do it regularly enough to have it quantified: what sort of timeframe do you allow for a) new hammer prep and fit, b) ongoing maintenance voicing, and c) special effort voicing for an important performer or event? There's a range, I know, depending... Can you give an honest naming of that range?

Thanks for the generosity of sharing your hard-won knowledge,

Chris



-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-17-2013 23:55
From: Fred Sturm
Subject: lacquer voicing

With respect to longevity of voicing in lacquered hammers, I think two things are key, beyond the initial set up (without excess lacquer, preferably without the entire hammer saturated).

First is maintenance crown voicing, which should be done with small enough diameter needles. Large needles are very destructive, and particularly to the felt right at the crown. I use #12 needles, the smallest readily available size (quilting needles), spaced 1.0 - 1.5 mm apart, extending 2 - 3 mm. I use them right in the string grooves when those have developed a bit and when the piano has developed an edge to the tone. The first time it will be one insertion perpendicular to the hammer, one per every string groove (quite fast, 20 minutes or less should do the whole piano). This will, in fact, reverse some of the packing of felt, making the grooves less apparent visually. And the tonal result is obvious, immediate, but subtle: it tends to be enough without the danger of going too far.

After a filing or two, it will usually be necessary to expand that procedure a bit, and, using the same tool, go at each groove from 1 and 11 o'clock, a bit of cross needling (though it is quite shallow). This kind of maintenance needling is quite stable as such things go, and it is minimally destructive to the fibers. (I'm not mentioning una corda voicing here, but that tends to be more stable for me because I have used bigger diameter, slightly longer needles initially, and because there is less packing from playing. But a similar regimen of maintenance voicing keeps that in good condition as well).

When this isn't sufficient, it is usually because you have worn down to the point that there is a broader profile of relatively heavily lacquered felt. At this point, standard upper crown needling of the sort one does with dense, unlacquered hammers comes into play. Insertions that come up to a point, that is to say that you work up the upper shoulder, and as you approach the center of the crown, you angle outwards, leaving the classic triangle point untouched (it is only touched by the small diameter needles, and only fairly shallowly). I generally use a 3 needle tool, #6 or so needles, 10 mm, and insert them fully (tapering this in the top 2 octaves - possibly only using smaller needles in the top octave). If the the 3 needle tool won't insert readily, there is too much lacquer. In which case you could use one needle, but you would probably be better served soaking some of the lacquer out in my experience. When there is too much lacquer, these maintenance procedures don't work nearly as well.

With this kind of consistent procedure (on hammers that have not been over-lacquered), I have found that both concert pianos and other heavy use pianos can be kept at a high level without hammer replacement for several years.

Interestingly I have 2 Bs in a piano faculty studio, one 20 year old lacquered, the other 5 - 6 year old Abels (relatively dense). The lacquered piano is used more (students play on that one). And it is more stable and has required less maintenance time - not a night and day difference by any means, but definitely more work for the Abels. I suspect that one more thorough shoulder needling will finally bring that one to a pretty stable state. 

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-17-2013 07:20
From: Andrew Saderman
Subject: lacquer voicing



I've worked quite a bit with Steinway hammers and have enjoyed the creative challenges in voicing them, however, would you agree, especially in an
institutional setting, that lacquered hammers require more maintenance than non lacquered? The more one plays on lacquered hammers the more the
deeper lacquered layers of felt comes up to the surface thereby having to constantly voice them. It seems, depending on the hammer, that is not so much the case with heat compressed hammers. Your thoughts?
-------------------------------------------
Andrew Saderman
Forest Hills NY
718-263-6508
-------------------------------------------

Just to focus on one particular question raised by Chris Brown:
"Have you tried the corollary of that, where the tension layer is reinforced, instead of the compression area, so that the center is softer, becoming harder the harder it is played?"

This would be hardening the shoulders, applying lacquer there and not at all to the crown. Yes, done that. Didn't work. It is what George Defebaugh was teaching as Steinway tech rep in the early 80s. Frustrated the heck out of me. It seems like it might work, but I think that center area simply isn't dense enough for it to be effective. As David Love points out, a lower profile (less felt between molding and strikepoint) would work far better (tension and compression being equal), as in that case the density of felt wouldn't need to be as high, since there would be less of it to compress with the hammer blow. But that thick a layer of (relatively) soft felt (in the current Steinway design) simply won't become hard enough with hard play. Also, possibly with a lighter hammer and a higher ratio that might work (partly because - I think - of the higher hammer velocities involved), but that's not what we are faced with.

In fact, that philosophy of hardening shoulders seems to survive at Steinway today, as evidenced by Ben Gac's photos of lines of hardener on the upper shoulders. In my own experience, until I came to realize that it was the core that needed the hardening (originally achieved by simply drenching the hammers), I had little success. 

I do agree that this is a very complex array of possible variables, and it takes a lot of experimentation and practice to become at all proficient - and much of it needs to be practice on concert instruments which is a pretty scary proposition. Then again, it takes a complex procedure based on a lot of experimentation and practice to bring dense hammers to an acceptable condition, with a lot more physical hard work usually involved. Voicing is probably the most single difficult thing to learn, and at the same time is the procedure most of us have the least opportunity to practice. A real conundrum.

That is my motivation for trying to stimulate discussion, and trying to lay out what I think I have learned over the years into a systematic, repeatable approach, hoping to elicit responses that will carry us a little farther forward in understanding. I don't consider myself an expert, just someone with a fair amount of experience, both positive and negative, and an enquiring mind. 


-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-18-2013 15:44
From: Christopher Brown
Subject: lacquer voicing

Hi, all -

This is a terrific discussion, with so much content offered from so much earnest experience. My thanks to David and Fred, in particular, and to Ed and Ben and each of you who have spoken up. And my thanks especially for discussing this complex topic.

You have greatly augmented my arsenal of specifics to try and consider. In my career, concert tuning has been an sporadic duty. The same with dealing with lacquered hammers. But maybe there are more of us in this category than specialists, who are forced in the fray to personally master the challenges. So, first a brief rant (which has already been somewhat addressed by your offerings) and then a couple of questions to the experts. And finally, the useful two-bits I have to offer.

I can understand two good reasons for the adding solids model of hammer preparation, one addressing the need to project to the back of a large or acoustically challenged hall, and the other addressing (but maybe not?) the need to retard wear in the heavily played hammer. My main annoyance with it as the choice of Steinway & Sons, an industry leader and the maker of otherwise mostly (a couple of action item exceptions, topics for other discussions) excellent and exceptional pianos, is that it requires too much skill of the thousands of us technicians that service them to produce consistently excellent tonal results. Too much skill? Look at the old Steinway approach to tone building vs. the new. Look at Fred's approach vs. David's. Just look at the pictures Ben provided: a very neat job, generally, but full of questions for me as to how to get those techniques just right and how to best integrate the different variables into a wholly wonderful sounding piano voice. It's the challenging, expert end of our work, anyway, but solids added are hard to control, assess, and negotiate, i.e., they complicate things before they solve things.

Part of the rant is how long it takes, the early on commitments in the adding that take huge work to recover from if you don't get it quite right, and general difficulty in micro-managing hidden hard spots, only found by prodding soft-enough-already spots. This time/energy complaint, of course, has a serious counterpart in the dense, non-lacquered approach. Anyway, a lot of Steinways in our current era don't sound as good as it seems like they should, IMO. And that may be largely due to technician error, mea culpa. But, well, exactly. I try hard, put in the time, think hard, and try to listen hard (to others and the piano at hand), as due plenty of others do, while producing not-quite-what-we-were-hoping-for results.

And the advantages are mostly for the concert instrument. Fine. A specialty treatment, handled by specialists, for the special situation. But what about the general populous of pianos in the entire rest of the marketplace? End rant.

There are clearly different approaches to lacquering hammers that can have successful results. I imagine those in Fred's care compare favorably to those in David's care and vice versa. Both of your approaches seem to be variations on harden the core, with gradiants of increasingly softer material to the softest on surface. Have you tried the corollary of that, where the tension layer is reinforced, instead of the compression area, so that the center is softer, becoming harder the harder it is played? I suppose making the surface of that reinforced tension layer, the contact layer, sufficiently noise-reduced is the problem, but it might provide a very clear ppp tone and an equally powerful fff. Could a medium mix applied all around, the Stanwood compass needle approach for the surface, and side-needling in the center as needed have merit? Is this sort of the direction Steinway is heading in with lacquering both crown and shoulders?

A variant of that idea is lacquering the under-shoulders, just applying at the staple, limiting the upward wicking, but filling downward to the molding. I've had some success with that technique, both for very hard hammers and for overly soft hammers. In both cases, it seems to enhance their bounce properties, reducing noise content in the one and increasing power in the other. I think of it as being something for the bounce, flexing at the shoulders, to push against. I believe the Steinway through-threaded and twisted-tight staples serve this function, but most of the hammers I use (with the exception of Steinway hammers I am not replacing) either don't have staples or have "t" type staples.

I like the concept of David's approach, but I'm generally dealing with the already lacquered, not the newly-hung to be lacquered. So, thanks, Fred, for some insight into how best to cope with these.

Finally, from what Ben said, Steinway clearly has an emphasis on action prep, regulation, and hammer string mating. I share that sense of emphasis: the preparation behind how the hammer gets to, contacts, and bounces away from its strings is part of voicing the lacquered or unlacquered hammer. The recent string leveling / hammer-to-string fitting discussion covered the contact portion in great detail, but it should be noted that flaws in the foundation behind that fit or in the nature of the fit itself, limit and/or erode what the hammer itself can achieve. To that end, I have tools to help the industry achieve superior prep, regulation, and mating. They are regulation tools, but they are also voicing tools, including the protocols they have engendered. Particularly, the Squaring Platform, with its Hammer Square and Shank Traveler. They help both the skilled and the less skilled to the place where successful voicing can occur. I believe this is particularly important for the lacquered hammer.

Finally, significant time, in my experience, is needed to accomplish the voicing implementations talked about in this discussion. May I ask of those who do it regularly enough to have it quantified: what sort of timeframe do you allow for a) new hammer prep and fit, b) ongoing maintenance voicing, and c) special effort voicing for an important performer or event? There's a range, I know, depending... Can you give an honest naming of that range?

Thanks for the generosity of sharing your hard-won knowledge,

Chris



-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------

First let me say that I have advocated the application of lacquer on the side of the hammer directly between the crown and the molding for some time now. We had an exchange about this a few years ago on the old list and I posted a rather lengthy document on my approach to lacquering. It stated precisely what you are now saying that the goal in applying lacquer is precisely to produce the same consistency as a hammer that is opened up at the shoulders with needles. The lacquer is simply designed to artificially create and reinforce this classic upside down triangle of firm felt between the strike point and the molding. The shoulders should, I stated, remain flexible. As is the case with a non-lacquered hammer I can see no reason to stiffen that part of the hammer. So, leave the shoulders unlacquered and put the lacquer directly under the strike point between the strike point and the molding where it is needed. That seemed to be news to you then, that the lacquer and needle techniques could in fact achieve, to some degree, the same structural goal. I am glad you are now advocating the same approach as I believe it is the correct one. That will help to prevent some of the problems associated with a complete saturation of the hammer. Better it avoids the mistaken notion that it is the shoulders of the hammer that need reinforcing while the area under the crown should remain free of any hardening agents. I have seen that done on many occasions. It is ineffective and counterproductive. It should be noted that Steinway is now pre dipping the entire hammer in lacquer before they send it out, or they were when I last checked. I would order them undipped, which you can apparently do. Equally important is the type of lacquer that is used. Soft setting lacquers that do not have furniture finish type of hardeners in them are the best. Off the shelf lacquers such as those used on table tops, sanding sealers and other such products tend to form hard spots, are too rigid, continue to harden and can create noise problems, the una corda among them, because of the random hard spots that can form at various and unpredictable depths. It is rumored that the lacquer originally used in the factory for this purpose was, in fact, this type of lacquer. I don't know if that's true or not. The only soft setting lacquer currently being sold that I know of is from Pianotek, their Hammer Lac product. They are the only source that I am aware of for that type of lacquer as it is an unusual and atypical product. For typical lacquer uses, such as furniture finishing, it is inappropriate as it remains relatively rubbery when compared with normal products designed for that purpose. Applied from the side (both sides actually to insure penetration all the way to the center of the hammer) it should be the correct strength to achieve the goal in a single application. One may have to experiment on a sample or two to determine what that is. Strengths may vary for different sections. Typically the density requirements for hammers will increase through the scale. Often these hammers don't when in their raw state and so the strength of the application should graduate. With the Pianotek product that strength may vary from a 20% solution to a 50% solution depending on the thickness of the felt and its initial density. On non performance pianos where the amount of power required is less I would typically use a 20% solution in the lower part of the piano and a 30 or 40% solution in the upper part of the piano depending on how thick and how soft the felt is. I prefer lacquer thinner over acetone because it flashes off slower and penetration is better. I have changed my mind on that over the years. It should be noted that the Bacon felt process that is used on these hammers is fairly unreliable and inconsistencies in the density are common even within a single sheet. Repeated applications have a more difficult time penetrating and remain more on the surface. That will tend to create a reverse gradient, the outer layers becoming harder and the inner layers remaining, let's say, less hard. It should be allowed to creep up to the crown of the hammer or very near. If the lacquer doesn't reach the surface or close enough to the surface then the hammer may not achieve adequate power and you will have to decide whether to apply more to the area you missed which will be the very surface of the hammer. That's not a good thing generally. The tone will have greater stability if applied from the side and allowed to creep toward the surface. The circle that forms may be as big as a quarter in the bass and midrange, more like a dime in the low treble and when it gets toward the very top then applying it from the side gets more difficult to control and it will tend to just wick over the crown. Apply it slowly. Done from the side (as opposed to the shoulders) you will notice that you need a lot less material. That's a good thing. At any rate, a bit of noise after the application is better than a hammer which is still too weak. A light filing including breaking both edges (bass side edge especially) after it dries is advisable. Once completely cured (48 hours is best) then conventional needling techniques can be used with the exception that an opening of the lower shoulders is usually not required. If you have applied the lacquer carefully that part will not have become too rigid. To reduce power first needle above the 10:30 and 1:30 marks toward the crown and proceed cautiously as you would with an unlacquered hammer (that is the structural goal). Judicious and shallow crown needling as you have described or in whatever manner you prefer is the next order of business. You can often save a lot of work by simply shallow needling the entire strike point area with a multi needle tool (I use a tool with 6 or 7 fine needles in a row imbedded in the end of a 1/2" dowel which is then tapered to make the needles more visible to me. I'll try and post a picture). It can be used with the needles oriented across the string point or in line with the strings on a single string mark rolling it over the crown of the hammer. Set the felt with several firm blows against a block of wood or against the string while holding the string mute with your thumb or a piece of felt (better) to insure that the shallow needling is stable. After that polish the hammer surface with fine grit paper (600 - 1000). When that is completed then you can go through and start nit picking single strings and the una corda pedal in various positions. I like to test the una corda at various dynamic levels, not just pianissimo, because that's how many pianists use it. If you have used a hard setting lacquer your task will be more difficult as you will be hunting for little crystalline structures that have a way of migrating to the surface. I have attached a photo to this email response but don't think it will get through the censors. If I have time later I will navigate back through the web interface and try and post it, but no breath holding please. Anyway, back off the tangent, that is my procedure, FWIW. I still like to avoid lacquer whenever possible whatever my success rate at making it work. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Saturday, March 16, 2013 9:11 PM To: David Love Subject: Voicing: RE:lacquer voicing I'd like to address this statement by David Love: "I have had very few experiences with hammers lacquered enough to create the kind of power necessary on a D that didn't sooner than later develop problems associated with lacquer: noise, a difficult to control dynamic continuum, progressive hardening over time, strike point deterioration from the requirements of crown needling, lack of flexibility and resilience. If it does happen, it is the exception and not the rule. I don't think I'm the only one who holds that opinion among the very highly skilled and reputable concert technicians many of whom are eschewing the NYD hammer when given a chance." ....snip

Here's the picture of the voicing tool.  Made from a 1/2" dowel with a slot cut across the top with a hand saw to recieve the needles which are glued in with CA glue, clamped to squeeze the needles between the wood  while the glue cures. 

A small indention is created with the end of a bench sander which fits the thumb nicely. 

-------------------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
-------------------------------------------

Thank you, David, for taking the time to post this very cogent discussion of the aims/goals of using lacquer.  I have now a greatly enhanced understanding of the point of it all.  I'll be making the tool you posted, too, in addition to experimenting with soft-setting lacquer.  I'll try it first on some of my own "guinea pig" pianos.

-------------------------------------------
John Dorr, RPT
Institute Director, Chicago 2013
Montana Chapter 594
Helena, MT
406-594-1985

-------------------------------------------






Original Message:
Sent: 03-17-2013 01:41
From: David Love
Subject: lacquer voicing

Here's the picture of the voicing tool.  Made from a 1/2" dowel with a slot cut across the top with a hand saw to recieve the needles which are glued in with CA glue, clamped to squeeze the needles between the wood  while the glue cures. 

A small indention is created with the end of a bench sander which fits the thumb nicely. 

-------------------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
-------------------------------------------

I've been reading this thread over the last couple of days with great interest and feel compelled to contribute with new information I recently learned:

I had the privilege of attending Steinway's "Voicing and Tone Production" seminar (it's not tone "Building" anymore, it's "Production" for reasons that I hope will be clear by the end of my post) at the factory in New York only a couple of weeks ago and was astonished to learn that the method of applying lacquer to their hammers has significantly changed.  When I was originally trained in voicing Steinway hammers I was taught to first "fill 'er up" with lacquer, wait 24-48 hrs for it to dry, do a second application in a similar manner, wait again, apply again to the shoulders, wait again, then do another application to the crown of certain sections if needed.  This "tone building" procedure is outlined in Steinway's current manual--but it is now outdated.  If you apply this method to Steinway's current hammers you'll overharden them and freeze their elasticity.

Steinway is now dipping its hammers in a 7:1 lacquer thinner and lacquer (with ~12% solids) solution after they have been pressed.  After waiting 24 hours they dip the bass end and treble end in the lacquer again and wait for it to dry.  This leaves the hammers much closer to the desired sound goal that Steinway has in mind; from this point the hammers go into pianos for production or to the parts department for sale to piano technicians.  

Late in the voicing seminar--after much fuss about alignment, regulation, and string level/hammer fitting--we applied a lacquer solution to hammers in some sections to increase either the power/sustain or the attack/brilliance.  I'm attaching pictures so you can see just how little lacquer was actually used at this stage!  The solution was approximately a 4:1 thinner/lacquer mixture; a moderately thin line was applied to each shoulder for more power, and a thin line across the crown (usually only necessary in the high treble) for better attack.  The lacquer that was applied to the crown was "pounded in" by holding the cheek block above the hammers (with the action pulled) and repeated playing test blows.  This was intended to reduce the crystal ping that results from crown lacquering.  You'll also note from the pictures that no lacquer was applied to the left edge of the hammer, and may even be able to make out that the left corner is ever so slightly sanded (beveled is too strong of a word). Because the amount of lacquer that was used was so little it dried in approximately an hour or so, allowing us shoeshine sand and then re-evaluate and reapply if necessary.  Tangentially, it's worth pointing out that even Hamburg applies a 9:1 solution to the shoulders of its hammers in sections where they want more brilliance or power.

I've never used Pianotek's Hammer Lac; nearly every tech I've spoken with who has used it has not been able to utilize it in a manner in which they liked the results.  I purchase my lacquer from Walter Wurdack Company in St. Louis, the same company that Steinway buys all of its lacquer from.  When I call them to order a quart (sometimes the smallest amount they'll sell it in is a gallon) I specify that I want to purchase the same formula that Steinway uses for their voicing: water-white nitrocellulose lacquer.  They'll send the MSD Sheet if you request it, from which you can figure out the percent solids content.  The batch that I recently received had a slightly higher solids content than what Steinway typically uses.  No worries though; you can always tell how your mixture is by how quickly it penetrates the hammer and disappears.  Like in the pictures, ideally the lacquer solution does not dissipate into the felt too quickly.

I hope that this information is helpful in some way!  I certainly have adjusted the way that I voice new Steinway pianos and new Steinway hammers now.  

-Ben

-------------------------------------------
Ben Gac, RPT
Chicago Chapter
Ben@BensPianoTuning.com
630-291-5654
-------------------------------------------

Ben: Thank you for sharing that information. I have not tried the lacquer directly from Wurdack (though I do use their other products) but did have a discussion recently at WestPac III about the qualities of this lacquer and it being devoid of some hardening agents among other things. I can't say for myself whether that is the case or much else about it. I certainly have experienced Steinway hammers presumable treated with this product. They don't stand out as being superior to those that employ other methods or products, at least not to me. It is interesting to note that the 12% solids solution that you mention is about 1/2 the typical solids content for off the shelf paint store nitro cellulose lacquers which are usually about 23% (MacLac clear gloss for example). Not surprisingly, when I used that product, which I have now abandoned, I used it in a much thinner solution than 7:1, not surprising. The Pianotek product seems to be even lower in solids as the strengths at which it is used are much greater than the 7:1 that you report. At 7:1 the Pianotek lacquer will have very little impact and so if people are using it at that strength it comes as no surprise that they have been disappointed with the results. I have used it on many sets of Bacon felt hammers with good and consistent results, but at a much higher concentration (30% that I suggested is almost 2:1). Even at 20%, a 4:1 ratio and quite strong by Steinway standards, it has a relatively mild effect. Just a point of reference, I mix my lacquers for this purpose by weight, so a 30% solution will be 30% lacquer by weight to 70% thinner. The question about whether the hammer should be soaked or the lacquer should be applied to the area where it is needed (between the crown of the hammer and the molding) remains. I don't agree with Steinway in this respect, as is evident. Whatever product is being used, I think the important point is that it is used at the proper strength for that particular product. The second issue about application location may well be a finer point since one can clearly do it both ways and make it work. The consequences in the short and long term for application location and product characteristics especially with respect to what happens when it hardens are the other important considerations. While Wurdack's lacquer may be what's used, I think it's clear that it is a special adapted use and not a use for which it was designed. David Love www.davidlovepianos.com
Original Message----- From: Ben Gac [mailto:noreply@egroups.ptg.org] Sent: Sunday, March 17, 2013 1:08 PM To: David Love Subject: Voicing: RE:lacquer voicing I've been reading this thread over the last couple of days with great interest and feel compelled to contribute with new information I recently learned: I had the privilege of attending Steinway's "Voicing and Tone Production" seminar (it's not tone "Building" anymore, it's "Production" for reasons that I hope will be clear by the end of my post) at the factory in New York only a couple of weeks ago and was astonished to learn that the method of applying lacquer to their hammers has significantly changed. When I was originally trained in voicing Steinway hammers I was taught to first "fill 'er up" with lacquer, wait 24-48 hrs for it to dry, do a second application in a similar manner, wait again, apply again to the shoulders, wait again, then do another application to the crown of certain sections if needed. This "tone building" procedure is outlined in Steinway's current manual--but it is now outdated. If you apply this method to Steinway's current hammers you'll overharden them and freeze their elasticity. Steinway is now dipping its hammers in a 7:1 lacquer thinner and lacquer (with ~12% solids) solution after they have been pressed. After waiting 24 hours they dip the bass end and treble end in the lacquer again and wait for it to dry. This leaves the hammers much closer to the desired sound goal that Steinway has in mind; from this point the hammers go into pianos for production or to the parts department for sale to piano technicians. Late in the voicing seminar--after much fuss about alignment, regulation, and string level/hammer fitting--we applied a lacquer solution to hammers in some sections to increase either the power/sustain or the attack/brilliance. I'm attaching pictures so you can see just how little lacquer was actually used at this stage! The solution was approximately a 4:1 thinner/lacquer mixture; a moderately thin line was applied to each shoulder for more power, and a thin line across the crown (usually only necessary in the high treble) for better attack. The lacquer that was applied to the crown was "pounded in" by holding the cheek block above the hammers (with the action pulled) and repeated playing test blows. This was intended to reduce the crystal ping that results from crown lacquering. You'll also note from the pictures that no lacquer was applied to the left edge of the hammer, and may even be able to make out that the left corner is ever so slightly sanded (beveled is too strong of a word). Because the amount of lacquer that was used was so little it dried in approximately an hour or so, allowing us shoeshine sand and then re-evaluate and reapply if necessary. Tangentially, it's worth pointing out that even Hamburg applies a 9:1 solution to the shoulders of its hammers in sections where they want more brilliance or power. I've never used Pianotek's Hammer Lac; nearly every tech I've spoken with who has used it has not been able to utilize it in a manner in which they liked the results. I purchase my lacquer from Walter Wurdack Company in St. Louis, the same company that Steinway buys all of its lacquer from. When I call them to order a quart (sometimes the smallest amount they'll sell it in is a gallon) I specify that I want to purchase the same formula that Steinway uses for their voicing: water-white nitrocellulose lacquer. They'll send the MSD Sheet if you request it, from which you can figure out the percent solids content. The batch that I recently received had a slightly higher solids content than what Steinway typically uses. No worries though; you can always tell how your mixture is by how quickly it penetrates the hammer and disappears. Like in the pictures, ideally the lacquer solution does not dissipate into the felt too quickly. I hope that this information is helpful in some way! I certainly have adjusted the way that I voice new Steinway pianos and new Steinway hammers now. -Ben ------------------------------------------- Ben Gac, RPT Chicago Chapter Ben@BensPianoTuning.com 630-291-5654 ------------------------------------------- [Non-text portions of this message have been removed]

Thanks so much, Ben for that report with photos! It is good to be brought up to date on the latest factory procedures. Did you notice any difference in density of the hammer felt, as some have reported, or does it feel similar under the needle?

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-17-2013 16:08
From: Ben Gac
Subject: lacquer voicing

I've been reading this thread over the last couple of days with great interest and feel compelled to contribute with new information I recently learned:

I had the privilege of attending Steinway's "Voicing and Tone Production" seminar (it's not tone "Building" anymore, it's "Production" for reasons that I hope will be clear by the end of my post) at the factory in New York only a couple of weeks ago and was astonished to learn that the method of applying lacquer to their hammers has significantly changed.  When I was originally trained in voicing Steinway hammers I was taught to first "fill 'er up" with lacquer, wait 24-48 hrs for it to dry, do a second application in a similar manner, wait again, apply again to the shoulders, wait again, then do another application to the crown of certain sections if needed.  This "tone building" procedure is outlined in Steinway's current manual--but it is now outdated.  If you apply this method to Steinway's current hammers you'll overharden them and freeze their elasticity.

Steinway is now dipping its hammers in a 7:1 lacquer thinner and lacquer (with ~12% solids) solution after they have been pressed.  After waiting 24 hours they dip the bass end and treble end in the lacquer again and wait for it to dry.  This leaves the hammers much closer to the desired sound goal that Steinway has in mind; from this point the hammers go into pianos for production or to the parts department for sale to piano technicians.  

Late in the voicing seminar--after much fuss about alignment, regulation, and string level/hammer fitting--we applied a lacquer solution to hammers in some sections to increase either the power/sustain or the attack/brilliance.  I'm attaching pictures so you can see just how little lacquer was actually used at this stage!  The solution was approximately a 4:1 thinner/lacquer mixture; a moderately thin line was applied to each shoulder for more power, and a thin line across the crown (usually only necessary in the high treble) for better attack.  The lacquer that was applied to the crown was "pounded in" by holding the cheek block above the hammers (with the action pulled) and repeated playing test blows.  This was intended to reduce the crystal ping that results from crown lacquering.  You'll also note from the pictures that no lacquer was applied to the left edge of the hammer, and may even be able to make out that the left corner is ever so slightly sanded (beveled is too strong of a word). Because the amount of lacquer that was used was so little it dried in approximately an hour or so, allowing us shoeshine sand and then re-evaluate and reapply if necessary.  Tangentially, it's worth pointing out that even Hamburg applies a 9:1 solution to the shoulders of its hammers in sections where they want more brilliance or power.

I've never used Pianotek's Hammer Lac; nearly every tech I've spoken with who has used it has not been able to utilize it in a manner in which they liked the results.  I purchase my lacquer from Walter Wurdack Company in St. Louis, the same company that Steinway buys all of its lacquer from.  When I call them to order a quart (sometimes the smallest amount they'll sell it in is a gallon) I specify that I want to purchase the same formula that Steinway uses for their voicing: water-white nitrocellulose lacquer.  They'll send the MSD Sheet if you request it, from which you can figure out the percent solids content.  The batch that I recently received had a slightly higher solids content than what Steinway typically uses.  No worries though; you can always tell how your mixture is by how quickly it penetrates the hammer and disappears.  Like in the pictures, ideally the lacquer solution does not dissipate into the felt too quickly.

I hope that this information is helpful in some way!  I certainly have adjusted the way that I voice new Steinway pianos and new Steinway hammers now.  

-Ben

-------------------------------------------
Ben Gac, RPT
Chicago Chapter
Ben@BensPianoTuning.com
630-291-5654
-------------------------------------------

In answer to your question about the felt feeling more dense, Fred: I suppose that the difference has never been great enough to cause my conscious mind to delineate a difference. I suppose that when I squeeze the shoulders that there is a little less give, but I suspect that may be a little more due to the pre-lacquering than a denser felt. I will note, however, that I notice a resiliency in the fibers when needling. I suspect that this is because the hammer is brand new. They still do not feel like anything close to what we label as "compression" hammers. It's probably worth mentioning that the new denser felt recipe that Steinway came up with a year or so ago is only being used on Ds and some Bs. All of the other models have kept the same felt density. I may be mistaken, but I believe that they pre-lacquer those sets of hammers as well. I personally have yet to see any of the new denser hammers in a D or B because these types of hammers are not yet in full production. For what it's worth, I too prefer to use nothing larger than a #7 needle when doing single needle voicing. When I do una corda voicing I prefer size 10 needles (quilting needles) arranged in a tool similar to the tools that you all have already described and pictured. -Ben ------------------------------------------- Ben Gac, RPT Chicago Chapter Ben@BensPianoTuning.com 630-291-5654 -------------------------------------------
Original Message: Sent: 03-17-2013 22:56 From: Fred Sturm Subject: lacquer voicing Thanks so much, Ben for that report with photos! It is good to be brought up to date on the latest factory procedures. Did you notice any difference in density of the hammer felt, as some have reported, or does it feel similar under the needle? ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------
Original Message: Sent: 03-17-2013 16:08 From: Ben Gac Subject: lacquer voicing I've been reading this thread over the last couple of days with great interest and feel compelled to contribute with new information I recently learned: I had the privilege of attending Steinway's "Voicing and Tone Production" seminar (it's not tone "Building" anymore, it's "Production" for reasons that I hope will be clear by the end of my post) at the factory in New York only a couple of weeks ago and was astonished to learn that the method of applying lacquer to their hammers has significantly changed. When I was originally trained in voicing Steinway hammers I was taught to first "fill 'er up" with lacquer, wait 24-48 hrs for it to dry, do a second application in a similar manner, wait again, apply again to the shoulders, wait again, then do another application to the crown of certain sections if needed. This "tone building" procedure is outlined in Steinway's current manual--but it is now outdated. If you apply this method to Steinway's current hammers you'll overharden them and freeze their elasticity. Steinway is now dipping its hammers in a 7:1 lacquer thinner and lacquer (with ~12% solids) solution after they have been pressed. After waiting 24 hours they dip the bass end and treble end in the lacquer again and wait for it to dry. This leaves the hammers much closer to the desired sound goal that Steinway has in mind; from this point the hammers go into pianos for production or to the parts department for sale to piano technicians. Late in the voicing seminar--after much fuss about alignment, regulation, and string level/hammer fitting--we applied a lacquer solution to hammers in some sections to increase either the power/sustain or the attack/brilliance. I'm attaching pictures so you can see just how little lacquer was actually used at this stage! The solution was approximately a 4:1 thinner/lacquer mixture; a moderately thin line was applied to each shoulder for more power, and a thin line across the crown (usually only necessary in the high treble) for better attack. The lacquer that was applied to the crown was "pounded in" by holding the cheek block above the hammers (with the action pulled) and repeated playing test blows. This was intended to reduce the crystal ping that results from crown lacquering. You'll also note from the pictures that no lacquer was applied to the left edge of the hammer, and may even be able to make out that the left corner is ever so slightly sanded (beveled is too strong of a word). Because the amount of lacquer that was used was so little it dried in approximately an hour or so, allowing us shoeshine sand and then re-evaluate and reapply if necessary. Tangentially, it's worth pointing out that even Hamburg applies a 9:1 solution to the shoulders of its hammers in sections where they want more brilliance or power. I've never used Pianotek's Hammer Lac; nearly every tech I've spoken with who has used it has not been able to utilize it in a manner in which they liked the results. I purchase my lacquer from Walter Wurdack Company in St. Louis, the same company that Steinway buys all of its lacquer from. When I call them to order a quart (sometimes the smallest amount they'll sell it in is a gallon) I specify that I want to purchase the same formula that Steinway uses for their voicing: water-white nitrocellulose lacquer. They'll send the MSD Sheet if you request it, from which you can figure out the percent solids content. The batch that I recently received had a slightly higher solids content than what Steinway typically uses. No worries though; you can always tell how your mixture is by how quickly it penetrates the hammer and disappears. Like in the pictures, ideally the lacquer solution does not dissipate into the felt too quickly. I hope that this information is helpful in some way! I certainly have adjusted the way that I voice new Steinway pianos and new Steinway hammers now. -Ben ------------------------------------------- Ben Gac, RPT Chicago Chapter Ben@BensPianoTuning.com 630-291-5654 -------------------------------------------

"Creative challenges", that's a euphemistic way of putting it. I would absolutely agree with that and would further say that the life of a lacquered hammers is shorter for the reasons you mention. I would be cautious, however, about classifying non lacquered hammers as "heat compressed hammers" some are some are not or are to a lesser degree. Heat is one of the things that destroys resilience and tension. It's misuse occurs both in the pre pressing process (creasing the felt before the molding in inserted into place, especially if excessive heat is used in conjunction with leaving the prepress in too long--the sheet of felt can be completely ruined), as well as the post pressing process in which heat is used in the outer calls to add density. This can destroy tension in the outer part of the hammer which is where the tension in the hammer exists. (The inner part of the hammer is under compression, the outer part of the hammer is under tension). The so-called cold pressed hammers (Ronsen still uses this method) do not use heat. Density can be added simply by applying controlled amounts of pressure to the outer cauls. This amount can be varied in different parts of the scale where different density requirements exist. With thinner felts density is added by the ability to employ greater amounts of stretching. Thicker or denser sheets of felt are more difficult to stretch and thus tend to have less tension. Poor quality felt that is not interlocked is limited in the amount of stretching and will tear at a certain point, thus poorer quality felts tend to be stretched less. Better felt (more interlocked) and thinner felt is capable of more stretching and the density achieved by stretching which produces tension will result in a more lively hammer. Also a more responsive one to voicing. Tension is ultimately released through the process of needling the outer layers of felt. Thus, a hammer which requires less needling out of the box will maintain its tension longer. Ironically, hammers that are made from denser felts or that are pressed to higher levels of density usually have less tension but require the most needling which is removing what little tension exists. Thus targeting just the right amount of density is very important so that the amount of needling and resulting tension loss can be minimized. Higher tension in a hammer produces a more stable voice and the "bouncy" quality will produce a rounder and better tone and will get the hammer off the string faster (important in the treble section to minimize the damping effect of the hammer and the filtering of upper partials). Tension is our friend in a hammer. The question of how deep needles need to penetrate if the goal is releasing tension (rather than simply altering density is a valid one and a topic for another day. Tension is also destroyed by gluing the outer layers together with lacquer or other products. It is also destroyed by steam applications--though usually steam is used as an extreme measure in hammers that have no tension anyway. Applying lacquer to the core of the hammer (where the hammer is compressed and not stretched) will help to preserve some tension in the outer part of the hammer where it may exists-if the hammer had tension to begin with. To your question, filing hammers not only removes the tensioned part of the hammer but puts you more in contact with the compressed part of the hammer that has now been infused with plastic. The character of the hammer will change as you progress through the outer layers. Not to say that we can't deal with that, but it becomes a different animal as you file away the outer layers. Of course a tensioned hammer becomes a different animal as well but in a different way. The tensioned felt starts to get replaced by less tensioned felt and more compressed felt. The difference, however, is that in the non lacquered hammer we are still dealing with felt. In the lacquered hammer we are dealing with a composite of some sort. Sorry for the tangential excursion. David Love www.davidlovepianos.com
Original Message----- From: Andrew Saderman [mailto:noreply@egroups.ptg.org] Sent: Sunday, March 17, 2013 4:20 AM To: David Love Subject: Voicing: RE:lacquer voicing I've worked quite a bit with Steinway hammers and have enjoyed the creative challenges in voicing them, however, would you agree, especially in an institutional setting, that lacquered hammers require more maintenance than non lacquered? The more one plays on lacquered hammers the more the deeper lacquered layers of felt comes up to the surface thereby having to constantly voice them. It seems, depending on the hammer, that is not so much the case with heat compressed hammers. Your thoughts? ------------------------------------------- Andrew Saderman Forest Hills NY 718-263-6508 -------------------------------------------

Thank you, David, for your very informative reply. I wasn't aware of all the detailed stages in the making of a hammer. Food for thought in dealing with both lacquered and non lacquered hammers. ------------------------------------------- Andrew Saderman Forest Hills NY 718-263-6508 -------------------------------------------
Original Message: Sent: 03-17-2013 10:02 From: David Love Subject: lacquer voicing "Creative challenges", that's a euphemistic way of putting it. I would absolutely agree with that and would further say that the life of a lacquered hammers is shorter for the reasons you mention. I would be cautious, however, about classifying non lacquered hammers as "heat compressed hammers" some are some are not or are to a lesser degree. Heat is one of the things that destroys resilience and tension. It's misuse occurs both in the pre pressing process (creasing the felt before the molding in inserted into place, especially if excessive heat is used in conjunction with leaving the prepress in too long--the sheet of felt can be completely ruined), as well as the post pressing process in which heat is used in the outer calls to add density. This can destroy tension in the outer part of the hammer which is where the tension in the hammer exists. (The inner part of the hammer is under compression, the outer part of the hammer is under tension). The so-called cold pressed hammers (Ronsen still uses this method) do not use heat. Density can be added simply by applying controlled amounts of pressure to the outer cauls. This amount can be varied in different parts of the scale where different density requirements exist. With thinner felts density is added by the ability to employ greater amounts of stretching. Thicker or denser sheets of felt are more difficult to stretch and thus tend to have less tension. Poor quality felt that is not interlocked is limited in the amount of stretching and will tear at a certain point, thus poorer quality felts tend to be stretched less. Better felt (more interlocked) and thinner felt is capable of more stretching and the density achieved by stretching which produces tension will result in a more lively hammer. Also a more responsive one to voicing. Tension is ultimately released through the process of needling the outer layers of felt. Thus, a hammer which requires less needling out of the box will maintain its tension longer. Ironically, hammers that are made from denser felts or that are pressed to higher levels of density usually have less tension but require the most needling which is removing what little tension exists. Thus targeting just the right amount of density is very important so that the amount of needling and resulting tension loss can be minimized. Higher tension in a hammer produces a more stable voice and the "bouncy" quality will produce a rounder and better tone and will get the hammer off the string faster (important in the treble section to minimize the damping effect of the hammer and the filtering of upper partials). Tension is our friend in a hammer. The question of how deep needles need to penetrate if the goal is releasing tension (rather than simply altering density is a valid one and a topic for another day. Tension is also destroyed by gluing the outer layers together with lacquer or other products. It is also destroyed by steam applications--though usually steam is used as an extreme measure in hammers that have no tension anyway. Applying lacquer to the core of the hammer (where the hammer is compressed and not stretched) will help to preserve some tension in the outer part of the hammer where it may exists-if the hammer had tension to begin with. To your question, filing hammers not only removes the tensioned part of the hammer but puts you more in contact with the compressed part of the hammer that has now been infused with plastic. The character of the hammer will change as you progress through the outer layers. Not to say that we can't deal with that, but it becomes a different animal as you file away the outer layers. Of course a tensioned hammer becomes a different animal as well but in a different way. The tensioned felt starts to get replaced by less tensioned felt and more compressed felt. The difference, however, is that in the non lacquered hammer we are still dealing with felt. In the lacquered hammer we are dealing with a composite of some sort. Sorry for the tangential excursion. David Love www.davidlovepianos.com

Original Message----- From: David Love >>Are you saying that the power that you want out of the box on a practice room piano is the same as what you want in a concert piano? Greetings, Not exactly. I might want the same power, but certainly not the same loudness. They are two different things. What I want for the practice rooms is soft of optimum, what I want to start out on the concert piano is too hard for optimum. I voice for as wide a range of tone as I can. Unlike the practice rooms, the concert pianos have to sacrifice some of the softest, most muted, tone in order to have enough power for distant listeners. In the practice rooms, I voice for durability, which, it seems, comes from a very soft shoulder. This makes the beginning of the hammers life quite mellow, Though after the first year, there is no shortage of brilliance and the needle games begin. The way the Weikert hammers sound out of the box is close to what I want, but I find that without some needle work, they brighten up too quickly. They have a fullness that I don't hear in other hammers. I am learning that the brilliance needed to produce "power" comes on its own, quickly, and how I needle them before it does has some bearing on how fast, and how far that brilliance occurs. I usually put up with student comments like, "weak action", "dead", "heavy" for the first three weeks of a new hammers life, then the pianos start getting used first. I can give the stage pianos that softness, but I will either hear howls from the faculty that likes "power", or it will be so crown oriented that it will disappear like a light switch turned off as soon as the note is played above pp. With the NY hammers, I soak to the "too much" state and bring them back from there. I don't like doing that, and I rarely use those hammers. Others are much better suited to specific needs, like practice rooms. I have sets of Imadegawa hammers from the early eighties that are just coming to the end of their useful life. I never needled the crowns, but over the years have repeatedly softened the shoulders, gradually working in the 11:00 and 1:00 positions as their life fades. Ed Foote RPT http://www.piano-tuners.org/edfoote/well_tempered_piano.html

Great exchange. Thanks, guys.

Keith McGavern, RPT
Shawnee, Oklahoma, USA
tune-repair@allegiance.tv
-------------------------------------------

I agree, Keith. I think  this should be a 2 or 3 part article in the Journal, eh?  It's awesome knowledge for me at least.  I've tried many of these cook-books, with several different hammers.  My favorite is still the Abel Naturals.  Getting more education on the Steinway hammers I've installed is just golden! A new project on a Steinway M is just underway, although i just started tearing it all down today with new strings and bridgepins...we'll see if I have to go farther.

 I have yet to get a standard with the Steinway hammers.  They all are different.  The Abels are much better at knowing what you get.  I've only tried the Ronson's Wikert twice, so I'm too new with them to offer any advice. Once on a practice Mason and Hamlin, which was OK. The other was the ugly Baldwin D I keep bringing up!  I think that one needs to get rebuilt or retired out. It's, dangin it, 60 years old with original soundboard and bridges with no plate stuffs done.  I know, I know. Nobody wants to spend the $$ on it. 

Too many bandaides never fixes a hip replacement!

Thanks, folks for the great extra education!!

Paul


-------------------------------------------
Paul T. Williams RPT
Piano Technician
University of Nebraska
Lincoln, NE 68588-0100
pwilliams4@unl.edu
-------------------------------------------






Original Message:
Sent: 03-18-2013 11:54
From: Keith McGavern
Subject: lacquer voicing

Great exchange. Thanks, guys.

Keith McGavern, RPT
Shawnee, Oklahoma, USA
tune-repair@allegiance.tv
-------------------------------------------

I agree and echo your opinion, Paul, on the Abel Naturals. The times I've installed in a few actions, they were practically perfect out of the box with very little needling or voicing up. For me, particularly as a college tech, consistency is the most important aspect of hammer work. Sorry if I strayed from the conversation at hand but just wanted to express my opinion about these hammers. ------------------------------------------- Andrew Saderman Forest Hills NY 718-263-6508 -------------------------------------------
Original Message: Sent: 03-18-2013 16:02 From: Paul Williams Subject: lacquer voicing I agree, Keith. I think this should be a 2 or 3 part article in the Journal, eh? It's awesome knowledge for me at least. I've tried many of these cook-books, with several different hammers. My favorite is still the Abel Naturals. Getting more education on the Steinway hammers I've installed is just golden! A new project on a Steinway M is just underway, although i just started tearing it all down today with new strings and bridgepins...we'll see if I have to go farther. I have yet to get a standard with the Steinway hammers. They all are different. The Abels are much better at knowing what you get. I've only tried the Ronson's Wikert twice, so I'm too new with them to offer any advice. Once on a practice Mason and Hamlin, which was OK. The other was the ugly Baldwin D I keep bringing up! I think that one needs to get rebuilt or retired out. It's, dangin it, 60 years old with original soundboard and bridges with no plate stuffs done. I know, I know. Nobody wants to spend the $$ on it. Too many bandaides never fixes a hip replacement! Thanks, folks for the great extra education!! Paul ------------------------------------------- Paul T. Williams RPT Piano Technician University of Nebraska Lincoln, NE 68588-0100 pwilliams4@unl.edu -------------------------------------------
Original Message: Sent: 03-18-2013 11:54 From: Keith McGavern Subject: lacquer voicing Great exchange. Thanks, guys. Keith McGavern, RPT Shawnee, Oklahoma, USA tune-repair@allegiance.tv -------------------------------------------

I'll have to say that I disagree with that conclusion but will have to elaborate at a later time when I have some additional data. David Love www.davidlovepianos.com I'm not sure I believe that it is possible for a hammer to be made so that it has the necessary bite for this application without needing either considerable shoulder needling or considerable core hardening. Lower the expectation of "bite and brilliance" and maybe it will be possible. The concert instrument is a special case, and it is a real shame that it tends to drive the design and treatment of smaller instruments, which are usually better off with a different kind of set up. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

This is somewhat tangential but I'll risk it. While I think that (see Fred's quote below) is an effective strategy in the treble, it is not in the bass. The bass needs mass otherwise the higher ratio combined with lightweight hammer will produce lots of upper partials but not that much fundamental. Not good. A steeper strike weight curve than has been sanctioned by the current strike weight zones on the Stanwood Smart Charts is what is needed, in my opinion of course--all due respect to Mr. Stanwood. I think tone should drive all hammer decisions and touchweight should follow. We can always adjust the ratios and deal with touchweight problems, that's easy. Once we decide on hammer characteristics that lock us in to a tonal direction we are much more limited in scope, especially as far as it is driven by the contributing factor of weight. Higher strike weights in the bass but a relatively steep dynamic density curve (that non-linear thing) so that when you do apply more force you do get consistently more upper partial development. Profile will be important there. Lower strike weights in the treble, and strike weights that are kept low even if the strike weight in the bass rises with the needs of higher tension, greater mass, concert type bass strings. The currently published strike weight zones, while they may make it easier to produce more uniform actions in terms of touchweight and inertia from top to bottom, may not in fact be the best when tonal considerations are taken into account. In fact, I am of the strong opinion that they do not in the upper and lower zones make much sense tonally at all, at least generally. While I have not really quantified the amount of variation in SWs at the treble end that would be required by two pianos with, say, different impedance characteristics and/or scales, I am of the opinion that the acceptable range is much smaller than this current publications would suggest. On the other end of the keyboard, I can't see any instances where an 8 gram SW at note 1 would be that effective or desirable. My take on this is that the strike weights in the bass can vary somewhat more than in the treble because the string mass and tension varies more plus there can be quite a bit of difference in the impedance characteristics that may require more mass to develop low fundamentals. But in the treble the range is quite small, certainly much smaller. As the Bass SW requirements swing up and down some, the treble requirements do not. Keeping the treble end hammers relatively light you will get more volume and more clarity with less noise. I realize there are some who will argue that this is subjective, and to some degree it is. But when you start looking at hammer string contact time as it relates to mass and the problems in the treble associated with excessive HSCT, it begins to look like a nearly 9 gram SW at note 88 (top high zone) will never be required even under the most extreme circumstances. At least not with pianos that we find in the real world or fall into the normal window of piano design. As an aside, but an important one, since the amount of inertia in the system is mostly a function of the hammer mass and the shank ratio (thank you Nick Gravagne for that insight), and since the uniformity of the touchweight dynamics of the action seem to be largely based on the range of inertia that we experience from one end of the keyboard to the other, then an argument can be made that in order to accommodate the tonal requirements of the piano as it relates to hammer mass while also being sensitive to the inertia curve from one end of the keyset to the other, that we may have to move toward a graduated action ratio: somewhat lower in the bass and somewhat higher in the treble. Makes sense to me the more I think about it and the slight difference in regulation specs would be something that pianists would, I believe, easily adapt to and probably not notice. The message, anyway, before I digress too much, is that tone and touch cannot be separated, but to the degree that they can, tone always trumps touch, at least in my book (coming soon I hope). David Love www.davidlovepianos.com ----------------------------- Also, possibly with a lighter hammer and a higher ratio that might work (partly because - I think - of the higher hammer velocities involved), but that's not what we are faced with. Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein

Good luck on that forth coming book, David.

I am certain it will be a best seller in the piano industry.

Keith McGavern, RPT
Shawnee, Oklahoma, USA
tune-repair@allegiance.tv

Original Message:
Sent: 03-18-2013 20:13
From: David Love
...  tone always trumps touch, at least in my book (coming soon I hope). ...

A bit tongue in cheek really. I am working on an article based on what I tried to communicate at WestPacIII and very related to this topic. Somewhat overly ambitious, I discovered given the time frame, but hopefully those who attended benefitted. Some clarifications and elaborations are necessary, I feel, and so I am working on that. A book? Not likely, but these things sometimes do take on a life of their own. Yes, a good editor is always important, as you can tell from my rather hastily written posts. David Love www.davidlovepianos.com
Original Message----- From: Keith McGavern [mailto:noreply@egroups.ptg.org] Sent: Monday, March 18, 2013 5:21 PM To: David Love Subject: Voicing: RE:lacquer voicing Good luck on that forth coming book, David. I am certain it will be a best seller in the piano industry. Keith McGavern, RPT Shawnee, Oklahoma, USA tune-repair@allegiance.tv -------------------------------------------

I wanted to comment on this even though it's a bigger topic than I can address in this post. It was something I addressed in my presentation at WestPac on the principles of voicing but probably needed further elaboration and possibly demonstration, difficult to do in that setting. I agree that it is the single most difficult thing to learn. There are several reasons for that, varying personal tastes being not the least. But I think the greatest difficulty lies in the fact that voicing is taught procedurally rather than structurally. We learn to stick needles here or there, apply lacquer here or there, this seems to work or that seems to work, try this, try that, we learn a technique for the Blue Point, one for the Natural, a different one for the Weickert, we hear various things about opening up, closing up, shock absorbers, triangles (with kinds of vertical orientations), one o'clock, three o'clock, needle length, diameter, special tools and on and on. It's no wonder we are confused. But we are not taught about the structural goals in the hammer, what we are after, how a properly functioning hammer works, what differentiates the inner and outer structure of different types of hammers, what problems these different types of hammers present in achieving those goals, how different types of hammers will respond to those attempts and subtle differences in how we need tailor our approach depending on what we find but always with a particular structural goal in mind. Of course, that structural goal should be something we look at before we ever get to the point of voicing, like when we choose the hammer in the first place. But as the lacquer discussion is suggesting, even with seemingly disparate procedures such as needles and lacquer, the structural goals are basically the same. Tension, no tension, too much density, not enough, some various combinations of those, our first job is structurally diagnostic, the mechanics follow. Once we understand that, the mechanics of voicing are relatively easy to grasp, not difficult to accomplish, and actually make sense. The lacquer discussion is a great example of that. Then it is a matter of refining, preceded by proper prep work, of course. But most hammer voicing classes spend so much time on the prep work that they never get to the meat of the subject. Not to dismiss the importance of pre voicing set up, it clearly is important, but putting air in the tires and checking the oil and gas won't get you where you want to go. At some point you have to put it in gear and start driving. And you better know where you want to end up. Also, we are not taught diagnostic listening. Yes, that is more difficult. To hear into the inner structure of the hammer and respond accordingly. Seems Yoda like, but it isn't. Most of us just pull out the lacquer or the needles and start in. That our hearing can tell us what is going on inside the hammer is critical!!! It saves us a lot of dead ends, saves the hammer unwanted and unneeded intrusions, lengthens its productive life and might save us from shoulder surgery. Without that we taking a stab in the dark, literally. It is difficult to learn, I admit, but if the goal isn't there to begin with you will never learn to focus and listen that way. David Love www.davidlovepianos.com Voicing is probably the most single difficult thing to learn, and at the same time is the procedure most of us have the least opportunity to practice. A real conundrum. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

One of the reasons any discussion of voicing is frustrating at best lies in the fact that we really don't understand anywhere near fully the interaction of the hammer and string, and exactly how that results in the tonal results we hear. The explanations we make are always incomplete and often at odds with the facts.

For example, we like to think of the hammer having a "springiness" as the result of which it may "bounce off" the string faster or "dwell on" the string longer depending on the force of the blow. How do we resolve that mental image with the high-speed Kawai video Don Mannino often shows:

1 hammer strikes string;
2 string is impelled upward, leaving the hammer, while the hammer continues to rise;
3 string comes back down, meeting the hammer, and the hammer almost stops moving upward while the string again moves upward leaving the hammer;
4 string comes down and meets the hammer, stopping the upward motion of the hammer, and string again moves upward;
5 a final meeting of the string and hammer results in the hammer descending fairly rapidly.

I've seen that video a few times, and for me it has raised far more questions than it has answered (what if the string were longer/shorter, the hammer were heavier/lighter, hammer surface softer/harder, hammer blow more/less forceful? just to mention a few), but one thing is clear: the hammer does not, in fact, either "bounce off" or "dwell on" the string. The interaction is far more complicated than that.

Another puzzling factor is just how the tonal spectrum is generated "in the string," the mix of partials. We know, more or less, that the hammer blow deforms the more or less straight line of the string at tension, creating a curve in the wire at the point of impact. That deformation is propagated in both directions, in a wave-like way, reflecting against both terminations, and the reflection from the agraffe/capo follows the wave moving toward the bridge. That complex wave reflects back and forth, causing the end of the wire that contacts the bridge pin to "jiggle" and set the bridge/soundboard in motion. After an initial "chaotic" phase (less than a second in general), this back and forth reflecting wave pattern resolves into a more or less harmonic structure (the partials become distinct and relatively harmonic). These things can be seen visually in some high speed videos Stephen Birkett was kind enough to post.

How do these "activities" of the wire relate to the complex interaction of the hammer and string in the Kawai/Mannino video? What do the multiple contacts of hammer and string do to the propagated wave(s)? How is the balance of different partials related to this? The number of questions far exceeds the number of answers.

Some things we do know, such as the general effect of mass: a heavier hammer will be able to create more of a deformation in the string and will also be more difficult/slower to stop. So that interaction of hammer and string illustrated in the Mannino/Kawai video will probably be longer and involve more touches on average of string and hammer.

To get more specifically to what all this means for us in our practical voicing, we know that Steinway hammers have become significantly and progressively heavier over the last century, and apparently that process continues today. In examining hammers from, say, 20 - 30 year periods, we can see that pretty dramatically, and weighing them confirms what we see. The felt itself has changed in look and feel to some extent, but modern un-lacquered felt seems to me (feeling, sticking in needles) to be about the same general density as those older hammers, at least in the same ballpark. But there is lots more of it. So to the extent there are spaces between fibers in the crown area, those are multiplied farther when the hammer impacts (it squishes together more, just taking up that space and compressing it).

Steinway also makes essentially the same piano in Hamburg, with essentially the same mass hammers, but those hammers are much denser. I don't have any access to early Hamburg hammers, but I suspect the ones 50 and 75 years ago were smaller and less dense, more or less proportional to NY hammers.

If we want, we can look on this as an experiment, undertaken in real time on real pianos. What happens when you add a lot of felt and mass to a hammer? It moves the string more, has more fundamental, and has less high partials. (We can also experiment in the same way for just the mass factor using Stanwood's binder clip method). How do you make the heavier hammer have more high partials, give it the ability to have a rising tonal gradient? Well, we and Steinway technicians have been experimenting with what works for lo, these many years, and the process continues.


-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-18-2013 22:25
From: David Love
Subject: lacquer voicing

I wanted to comment on this even though it's a bigger topic than I can address in this post. It was something I addressed in my presentation at WestPac on the principles of voicing but probably needed further elaboration and possibly demonstration, difficult to do in that setting.

I agree that it is the single most difficult thing to learn. There are several reasons for that, varying personal tastes being not the least.

But I think the greatest difficulty lies in the fact that voicing is taught procedurally rather than structurally.

We learn to stick needles here or there, apply lacquer here or there, this seems to work or that seems to work, try this, try that, we learn a technique for the Blue Point, one for the Natural, a different one for the Weickert, we hear various things about opening up, closing up, shock absorbers, triangles (with kinds of vertical orientations), one o'clock, three o'clock, needle length, diameter, special tools and on and on. It's no wonder we are confused. But we are not taught about the structural goals in the hammer, what we are after, how a properly functioning hammer works, what differentiates the inner and outer structure of different types of hammers, what problems these different types of hammers present in achieving those goals, how different types of hammers will respond to those attempts and subtle differences in how we need tailor our approach depending on what we find but always with a particular structural goal in mind. Of course, that structural goal should be something we look at before we ever get to the point of voicing, like when we choose the hammer in the first place. But as the lacquer discussion is suggesting, even with seemingly disparate procedures such as needles and lacquer, the structural goals are basically the same. Tension, no tension, too much density, not enough, some various combinations of those, our first job is structurally diagnostic, the mechanics follow.

Once we understand that, the mechanics of voicing are relatively easy to grasp, not difficult to accomplish, and actually make sense. The lacquer discussion is a great example of that. Then it is a matter of refining, preceded by proper prep work, of course. But most hammer voicing classes spend so much time on the prep work that they never get to the meat of the subject. Not to dismiss the importance of pre voicing set up, it clearly is important, but putting air in the tires and checking the oil and gas won't get you where you want to go. At some point you have to put it in gear and start driving. And you better know where you want to end up.

Also, we are not taught diagnostic listening. Yes, that is more difficult. To hear into the inner structure of the hammer and respond accordingly. Seems Yoda like, but it isn't. Most of us just pull out the lacquer or the needles and start in. That our hearing can tell us what is going on inside the hammer is critical!!! It saves us a lot of dead ends, saves the hammer unwanted and unneeded intrusions, lengthens its productive life and might save us from shoulder surgery. Without that we taking a stab in the dark, literally. It is difficult to learn, I admit, but if the goal isn't there to begin with you will never learn to focus and listen that way.

David Love
www.davidlovepianos.com

Voicing is probably the most single difficult thing to learn, and at the same time is the procedure most of us have the least opportunity to practice. A real conundrum.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------

I forgot to add the final thing I was leading up to in my last post:

Experience has seemed to show, both in the Hamburg and NYC models, that successful hammers (of modern mass, modern design Ds) will need to have a very dense (Hamburg) or very stiff (NY) core, the area around the end of the wooden hammer molding, as a starting point to create any brilliance (high partial predominance in the mix), and that the tonal spectrum for varied force of blow, and for any given force of blow will be enhanced by having shoulders that are fairly flexible (and one can emulate that using dense Renner or Abel hammers, or lacquered softer hammers, of the same general mass). That is what has been learned empirically - at least that is what I gather from what I hear from others and what my own results have been.

As for a theory of why and how this happens, I really am at a loss for a good model that syncs with the inescapable "facts" outlined in my previous post. I want to know, but I am also partly content with "knowing what works." That's what pays the bills.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 14:53
From: Fred Sturm
Subject: lacquer voicing

One of the reasons any discussion of voicing is frustrating at best lies in the fact that we really don't understand anywhere near fully the interaction of the hammer and string, and exactly how that results in the tonal results we hear. The explanations we make are always incomplete and often at odds with the facts.

For example, we like to think of the hammer having a "springiness" as the result of which it may "bounce off" the string faster or "dwell on" the string longer depending on the force of the blow. How do we resolve that mental image with the high-speed Kawai video Don Mannino often shows:

1 hammer strikes string;
2 string is impelled upward, leaving the hammer, while the hammer continues to rise;
3 string comes back down, meeting the hammer, and the hammer almost stops moving upward while the string again moves upward leaving the hammer;
4 string comes down and meets the hammer, stopping the upward motion of the hammer, and string again moves upward;
5 a final meeting of the string and hammer results in the hammer descending fairly rapidly.

I've seen that video a few times, and for me it has raised far more questions than it has answered (what if the string were longer/shorter, the hammer were heavier/lighter, hammer surface softer/harder, hammer blow more/less forceful? just to mention a few), but one thing is clear: the hammer does not, in fact, either "bounce off" or "dwell on" the string. The interaction is far more complicated than that.

Another puzzling factor is just how the tonal spectrum is generated "in the string," the mix of partials. We know, more or less, that the hammer blow deforms the more or less straight line of the string at tension, creating a curve in the wire at the point of impact. That deformation is propagated in both directions, in a wave-like way, reflecting against both terminations, and the reflection from the agraffe/capo follows the wave moving toward the bridge. That complex wave reflects back and forth, causing the end of the wire that contacts the bridge pin to "jiggle" and set the bridge/soundboard in motion. After an initial "chaotic" phase (less than a second in general), this back and forth reflecting wave pattern resolves into a more or less harmonic structure (the partials become distinct and relatively harmonic). These things can be seen visually in some high speed videos Stephen Birkett was kind enough to post.

How do these "activities" of the wire relate to the complex interaction of the hammer and string in the Kawai/Mannino video? What do the multiple contacts of hammer and string do to the propagated wave(s)? How is the balance of different partials related to this? The number of questions far exceeds the number of answers.

Some things we do know, such as the general effect of mass: a heavier hammer will be able to create more of a deformation in the string and will also be more difficult/slower to stop. So that interaction of hammer and string illustrated in the Mannino/Kawai video will probably be longer and involve more touches on average of string and hammer.

To get more specifically to what all this means for us in our practical voicing, we know that Steinway hammers have become significantly and progressively heavier over the last century, and apparently that process continues today. In examining hammers from, say, 20 - 30 year periods, we can see that pretty dramatically, and weighing them confirms what we see. The felt itself has changed in look and feel to some extent, but modern un-lacquered felt seems to me (feeling, sticking in needles) to be about the same general density as those older hammers, at least in the same ballpark. But there is lots more of it. So to the extent there are spaces between fibers in the crown area, those are multiplied farther when the hammer impacts (it squishes together more, just taking up that space and compressing it).

Steinway also makes essentially the same piano in Hamburg, with essentially the same mass hammers, but those hammers are much denser. I don't have any access to early Hamburg hammers, but I suspect the ones 50 and 75 years ago were smaller and less dense, more or less proportional to NY hammers.

If we want, we can look on this as an experiment, undertaken in real time on real pianos. What happens when you add a lot of felt and mass to a hammer? It moves the string more, has more fundamental, and has less high partials. (We can also experiment in the same way for just the mass factor using Stanwood's binder clip method). How do you make the heavier hammer have more high partials, give it the ability to have a rising tonal gradient? Well, we and Steinway technicians have been experimenting with what works for lo, these many years, and the process continues.


-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-18-2013 22:25
From: David Love
Subject: lacquer voicing

I wanted to comment on this even though it's a bigger topic than I can address in this post. It was something I addressed in my presentation at WestPac on the principles of voicing but probably needed further elaboration and possibly demonstration, difficult to do in that setting.

I agree that it is the single most difficult thing to learn. There are several reasons for that, varying personal tastes being not the least.

But I think the greatest difficulty lies in the fact that voicing is taught procedurally rather than structurally.

We learn to stick needles here or there, apply lacquer here or there, this seems to work or that seems to work, try this, try that, we learn a technique for the Blue Point, one for the Natural, a different one for the Weickert, we hear various things about opening up, closing up, shock absorbers, triangles (with kinds of vertical orientations), one o'clock, three o'clock, needle length, diameter, special tools and on and on. It's no wonder we are confused. But we are not taught about the structural goals in the hammer, what we are after, how a properly functioning hammer works, what differentiates the inner and outer structure of different types of hammers, what problems these different types of hammers present in achieving those goals, how different types of hammers will respond to those attempts and subtle differences in how we need tailor our approach depending on what we find but always with a particular structural goal in mind. Of course, that structural goal should be something we look at before we ever get to the point of voicing, like when we choose the hammer in the first place. But as the lacquer discussion is suggesting, even with seemingly disparate procedures such as needles and lacquer, the structural goals are basically the same. Tension, no tension, too much density, not enough, some various combinations of those, our first job is structurally diagnostic, the mechanics follow.

Once we understand that, the mechanics of voicing are relatively easy to grasp, not difficult to accomplish, and actually make sense. The lacquer discussion is a great example of that. Then it is a matter of refining, preceded by proper prep work, of course. But most hammer voicing classes spend so much time on the prep work that they never get to the meat of the subject. Not to dismiss the importance of pre voicing set up, it clearly is important, but putting air in the tires and checking the oil and gas won't get you where you want to go. At some point you have to put it in gear and start driving. And you better know where you want to end up.

Also, we are not taught diagnostic listening. Yes, that is more difficult. To hear into the inner structure of the hammer and respond accordingly. Seems Yoda like, but it isn't. Most of us just pull out the lacquer or the needles and start in. That our hearing can tell us what is going on inside the hammer is critical!!! It saves us a lot of dead ends, saves the hammer unwanted and unneeded intrusions, lengthens its productive life and might save us from shoulder surgery. Without that we taking a stab in the dark, literally. It is difficult to learn, I admit, but if the goal isn't there to begin with you will never learn to focus and listen that way.

David Love
www.davidlovepianos.com

Voicing is probably the most single difficult thing to learn, and at the same time is the procedure most of us have the least opportunity to practice. A real conundrum.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------

Christopher: The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it. The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through). Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering. http://disanji.net/iOS_Doc/documentation/Cocoa/Conceptual/Animation_Types_Timing/Art/standardtiming.jpg ------------------------------------------- Christopher Brown Owner TPR Tools Littleton MA 978-486-0610 -------------------------------------------

Standard Timing photo attached to illustrate my previous post to Christopher Brown as I'm sure it got filtered.  If itposts correctly the one on the top right is what we are after, in my opinion, of course.

-------------------------------------------
David Love RPT
www.davidlovepianos.com
davidlovepianos@comcast.net
415 407 8320
-------------------------------------------

Hi David:
I'm lurking with great interest in this discussion because I'm like the deer-in-headlights trying to learn the ropes in voicing.  I've been to many "hands-on" classes where I simply mimicked the procedures given, and never understood what I was supposed to learn.  Your descriptions, along with Fred's, make more sense than anything I've heard.  This discussion should be in the next Journal. 
I'm sure that discussions of "Polar Voicing" "Angel Shot" voicing and other techniques have their place, but they are not the whole picture. 
Gradually I have begun to try to sort things out, and try to understand what everybody was trying to convey.  Especially when using hardeners in the felt, I've had many unexpected results. 
What makes this subject and practice so tricky is, if you make a mistake, you can ruin things in a hurry.  Like when you learn to tune, you encounter different situations with loose or tight pins, no bushings, lots of friction, etc., but you find ways to get it done.  It won't hurt the piano if you do it wrong.  But when you do voicing, you can do things that are difficult or impossible to reverse. 
I don't often do hammer jobs, but I did a Steinway M a year ago.  The hammers were hardly more than cotton balls, even though they were stock Steinway hammers which were pre-lacquered.  I used some store-bought lacquer and put it just above the moldings, as you describe.  It wasn't nearly enough, and subsequent attempts didn't do much.  Especially since it takes time to harden, and makes awful fumes in the home!  It might have been easier if I'd had the piano in my shop.  I ended up using keytop solution, and now the voicing is uneven.  Friggin' mess.  So, again, I'm trying to undo what I've done to some extent and hope to learn from this discussion where to go next. 
Keep it comin'
Paul McCloud
San Diego

Paul,
My best advice for your situation is to wash out the hardeners and start over. See my article in June, 2009 Journal, p 36, for details. (If you don't have access, tell me privately and I'll send you a pdf). I would use a mix of acetone and lacquer thinner, maybe half and half.

Once the hammers have dried, listen to them before doing anything. Sometimes they will be at a pretty good level, and I think that is because, while much washes out, some of the hardening material (lacquer solids and/or keytop and/or whatever else) has penetrated the fibers of the felt. In any case, decide what to do only after listening first. If they need a lot of brightening, I would apply lacquer at about 4% solids from the sides of the hammers at the tip of the molding (hypo oiler medium needle squirting there) and watch a circle of wet grow until it is maybe 3 mm from the surface. Do this to a couple hammers in the tenor and watch for a few seconds after you take the needle away to see how far the material continues to go, so you can judge when to stop. It is not a disaster if you reach the surface of the felt, especially in the top couple octaves, but I prefer that there be at least 1 mm and preferably 2 mm of unlacquered felt on the surface. Do from one side of each hammer in a section, turn the stack over and do from the other side (you need less from the second side, you are just making sure it is even).

Let dry (preferably at least a couple days, but at least overnight), listen to what it sounds like, and go from there. For the attack sound, you will likely need to add hardener to the surface at least in the top area (if the lacquer didn't get to the surface), and possibly elsewhere, but you are listening to how much the tonal gradient grows: does it have enough guts? If not, a second application is quite possible, either the same solids or perhaps a little less. I would avoid a third - have never needed one, but I think it would be counter-productive.

Easy enough for me to say, while you have this piano in the customer's house and in use. I realize the logistics would be troublesome, you would definitely need to take at least the stack to your shop, and probably back and forth at least a couple times. You don't want to have the lacquer fumes become an issue, but you have to be back at the piano and listen to know what to do next. I have been successful so far in the cases where I have washed out lacquer and started over, with at least acceptable results.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-18-2013 23:30
From: Paul McCloud
Subject: lacquer voicing

Hi David:
I'm lurking with great interest in this discussion because I'm like the deer-in-headlights trying to learn the ropes in voicing.  I've been to many "hands-on" classes where I simply mimicked the procedures given, and never understood what I was supposed to learn.  Your descriptions, along with Fred's, make more sense than anything I've heard.  This discussion should be in the next Journal. 
I'm sure that discussions of "Polar Voicing" "Angel Shot" voicing and other techniques have their place, but they are not the whole picture. 
Gradually I have begun to try to sort things out, and try to understand what everybody was trying to convey.  Especially when using hardeners in the felt, I've had many unexpected results. 
What makes this subject and practice so tricky is, if you make a mistake, you can ruin things in a hurry.  Like when you learn to tune, you encounter different situations with loose or tight pins, no bushings, lots of friction, etc., but you find ways to get it done.  It won't hurt the piano if you do it wrong.  But when you do voicing, you can do things that are difficult or impossible to reverse. 
I don't often do hammer jobs, but I did a Steinway M a year ago.  The hammers were hardly more than cotton balls, even though they were stock Steinway hammers which were pre-lacquered.  I used some store-bought lacquer and put it just above the moldings, as you describe.  It wasn't nearly enough, and subsequent attempts didn't do much.  Especially since it takes time to harden, and makes awful fumes in the home!  It might have been easier if I'd had the piano in my shop.  I ended up using keytop solution, and now the voicing is uneven.  Friggin' mess.  So, again, I'm trying to undo what I've done to some extent and hope to learn from this discussion where to go next. 
Keep it comin'
Paul McCloud
San Diego

Original Message ----- From: "Fred Sturm" To: "Paul McCloud" Sent: Tuesday, March 19, 2013 1:52:50 PM Subject: Voicing: RE:lacquer voicing Paul, My best advice for your situation is to wash out the hardeners and start over. See my article in June, 2009 Journal, p 36, for details. (If you don't have access, tell me privately and I'll send you a pdf). I would use a mix of acetone and lacquer thinner, maybe half and half. Once the hammers have dried, listen to them before doing anything. Sometimes they will be at a pretty good level, and I think that is because, while much washes out, some of the hardening material (lacquer solids and/or keytop and/or whatever else) has penetrated the fibers of the felt. In any case, decide what to do only after listening first. If they need a lot of brightening, I would apply lacquer at about 4% solids from the sides of the hammers at the tip of the molding (hypo oiler medium needle squirting there) and watch a circle of wet grow until it is maybe 3 mm from the surface. Do this to a couple hammers in the tenor and watch for a few seconds after you take the needle away to see how far the material continues to go, so you can judge when to stop. It is not a disaster if you reach the surface of the felt, especially in the top couple octaves, but I prefer that there be at least 1 mm and preferably 2 mm of unlacquered felt on the surface. Do from one side of each hammer in a section, turn the stack over and do from the other side (you need less from the second side, you are just making sure it is even). Let dry (preferably at least a couple days, but at least overnight), listen to what it sounds like, and go from there. For the attack sound, you will likely need to add hardener to the surface at least in the top area (if the lacquer didn't get to the surface), and possibly elsewhere, but you are listening to how much the tonal gradient grows: does it have enough guts? If not, a second application is quite possible, either the same solids or perhaps a little less. I would avoid a third - have never needed one, but I think it would be counter-productive. Easy enough for me to say, while you have this piano in the customer's house and in use. I realize the logistics would be troublesome, you would definitely need to take at least the stack to your shop, and probably back and forth at least a couple times. You don't want to have the lacquer fumes become an issue, but you have to be back at the piano and listen to know what to do next. I have been successful so far in the cases where I have washed out lacquer and started over, with at least acceptable results. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein ------------------------------------------- Thanks, Fred, for the detailed explanation. Someone reminded me that you had experience washing lacquer out of hammers. I'll look for that issue. Paul

I'm reposting this in plain text as the previous post went in HTML and is a mess. David Love www.davidlovepianos.com Christopher: The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it. The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through). Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering. ------------------------------------------- Christopher Brown Owner TPR Tools Littleton MA 978-486-0610 -------------------------------------------

Still a mess, somebody fix that. David Love www.davidlovepianos.com
Original Message----- From: David Love [mailto:noreply@egroups.ptg.org] Sent: Monday, March 18, 2013 8:08 PM To: David Love Subject: Voicing : lacquer voicing I'm reposting this in plain text as the previous post went in HTML and is a mess. David Love www.davidlovepianos.com Christopher: The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it. The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through). Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering. ------------------------------------------- Christopher Brown Owner TPR Tools Littleton MA 978-486-0610 -------------------------------------------

Thanks, Fred for your reply. I think I would prefer to work from one basic model of hammer preparation and the dense core, gradiant softening to surface model is a good one and plenty complex enough to work with, without me introducing extra variables. One reframed question to you, David, or anyone else who may have experience with this, does hardening from the staple down support this model, unnecessarily close off needling options that are useful, or just not make enough difference one way or the other?

And thanks, David, for offering us the upper right graph. It does seem to represent my hoped-for aspiration for hammer performance. One comment in your response intrigued me: "Applying drops of hardener to the strike point or shoulder only fails in concept." One pragmatic reading of this that I pretty much subscribe to might be: "What works, works - if something needs to happen, have an open mind as to the means, regardless of preconceptions". Yet we need a well-considered starting point / frame of reference. I think that you and Fred are describing a similar vision of what will lead most readily to the graphically-imagined result. But. What did you intend with that interesting, somewhat provocative inclusion?

CB

-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-18-2013 23:07
From: David Love
Subject: lacquer voicing

I'm reposting this in plain text as the previous post went in HTML and is a mess.

David Love
www.davidlovepianos.com

Christopher:

The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it.

The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through).

Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering.


-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------

Chris,
What precisely do you mean by "hardening from the staple down?" Only hardening in the very lowest shoulder below the staple? BTW, that has been done all along in Steinway hammer manufacture, as I understand, dipping the corners of the felt before pressing/gluing, initially with the grey whatever it was, and then, when the grey stuff was found to be toxic, just with lacquer.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 13:24
From: Christopher Brown
Subject: lacquer voicing

Thanks, Fred for your reply. I think I would prefer to work from one basic model of hammer preparation and the dense core, gradiant softening to surface model is a good one and plenty complex enough to work with, without me introducing extra variables. One reframed question to you, David, or anyone else who may have experience with this, does hardening from the staple down support this model, unnecessarily close off needling options that are useful, or just not make enough difference one way or the other?

And thanks, David, for offering us the upper right graph. It does seem to represent my hoped-for aspiration for hammer performance. One comment in your response intrigued me: "Applying drops of hardener to the strike point or shoulder only fails in concept." One pragmatic reading of this that I pretty much subscribe to might be: "What works, works - if something needs to happen, have an open mind as to the means, regardless of preconceptions". Yet we need a well-considered starting point / frame of reference. I think that you and Fred are describing a similar vision of what will lead most readily to the graphically-imagined result. But. What did you intend with that interesting, somewhat provocative inclusion?

CB

-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-18-2013 23:07
From: David Love
Subject: lacquer voicing

I'm reposting this in plain text as the previous post went in HTML and is a mess.

David Love
www.davidlovepianos.com

Christopher:

The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it.

The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through).

Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering.


-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------

Fred -

I apply it so that it does not reach the shoulders - applying with an oiler at the staple and below works well, wicking the lacquer all the way down to the molding. I didn't know that history, but the traditional dyed area is part of what gave me the notion. With non-lacquered hammers I have found it beneficial. But now I will be anticipating a chance to do the side lacquering above the molding. I have a D coming up that will offer an appropriate opportunity. It seems to me hardening both areas is compatible conceptually and you are saying that Steinway historically did that? Have you tried this approach? Any thoughts?

-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-19-2013 14:11
From: Fred Sturm
Subject: lacquer voicing

Chris,
What precisely do you mean by "hardening from the staple down?" Only hardening in the very lowest shoulder below the staple? BTW, that has been done all along in Steinway hammer manufacture, as I understand, dipping the corners of the felt before pressing/gluing, initially with the grey whatever it was, and then, when the grey stuff was found to be toxic, just with lacquer.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 13:24
From: Christopher Brown
Subject: lacquer voicing

Thanks, Fred for your reply. I think I would prefer to work from one basic model of hammer preparation and the dense core, gradiant softening to surface model is a good one and plenty complex enough to work with, without me introducing extra variables. One reframed question to you, David, or anyone else who may have experience with this, does hardening from the staple down support this model, unnecessarily close off needling options that are useful, or just not make enough difference one way or the other?

And thanks, David, for offering us the upper right graph. It does seem to represent my hoped-for aspiration for hammer performance. One comment in your response intrigued me: "Applying drops of hardener to the strike point or shoulder only fails in concept." One pragmatic reading of this that I pretty much subscribe to might be: "What works, works - if something needs to happen, have an open mind as to the means, regardless of preconceptions". Yet we need a well-considered starting point / frame of reference. I think that you and Fred are describing a similar vision of what will lead most readily to the graphically-imagined result. But. What did you intend with that interesting, somewhat provocative inclusion?

CB

-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-18-2013 23:07
From: David Love
Subject: lacquer voicing

I'm reposting this in plain text as the previous post went in HTML and is a mess.

David Love
www.davidlovepianos.com

Christopher:

The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it.

The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through).

Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering.


-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------

I am saying that Steinway has dipped the lower shoulders (from about staple down) as part of their hammer-making procedure all along. You don't see it now, because it is lacquer rather than the colored stuff. I was told they substituted because the grey stuff was toxic, an EPA compliance thing, or maybe OSHA. In any case, this is, as I understand it, more of a hammer-making procedure than a tone-affect-producing thing -  not that the wide-spread notion of stiffened shoulders as a "good thing" might not have stemmed partly from this procedure, done by other hammer-makers as well (and imitated with spray pain by several cheapo American manufacturers in the 50s - 70s).

I think it has to do with having a stiff bit of felt at the ends so it will accommodate to the hammer press better, something along those lines, giving more even hammers. BTW, I happened to be at Steinway NY fairly shortly after they started dipping whole sets of hammers in lacquer before they cut them apart. I was told that one reason for that was it allowed greater precision of cutting: stiffer felt and you are less likely to go astray, as often used to happen, resulting in adjacent hammers 1 mm or more different in width. And, indeed, hammers since then have been more consistent in width. And the voicers haven't had to do as much doping.

Practically speaking, no, I don't believe that stiffening shoulders of a set of Steinway hammers will produce good tonal results. Tried that, more than once, many times, didn't work. Period. Where you need lacquer the most is right at the tip of the molding, the felt between the tip of the molding and the crown. Whether you put it there from the sides or straight from the middle of the crown, that's where it is needed. I think it is a more rational and efficient process to go to the trouble of putting it in from the side, but it is quite workable to apply it from the top, and, indeed, to saturate the hammers. It just makes more work in opening up the shoulders, removing surface noise, evening out, etc. In the long run, putting it right where you need it is a more efficient procedure. You can always add more elsewhere (like the surface, to get more attack), if needed.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 18:03
From: Christopher Brown
Subject: lacquer voicing

Fred -

I apply it so that it does not reach the shoulders - applying with an oiler at the staple and below works well, wicking the lacquer all the way down to the molding. I didn't know that history, but the traditional dyed area is part of what gave me the notion. With non-lacquered hammers I have found it beneficial. But now I will be anticipating a chance to do the side lacquering above the molding. I have a D coming up that will offer an appropriate opportunity. It seems to me hardening both areas is compatible conceptually and you are saying that Steinway historically did that? Have you tried this approach? Any thoughts?

-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-19-2013 14:11
From: Fred Sturm
Subject: lacquer voicing

Chris,
What precisely do you mean by "hardening from the staple down?" Only hardening in the very lowest shoulder below the staple? BTW, that has been done all along in Steinway hammer manufacture, as I understand, dipping the corners of the felt before pressing/gluing, initially with the grey whatever it was, and then, when the grey stuff was found to be toxic, just with lacquer.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 13:24
From: Christopher Brown
Subject: lacquer voicing

Thanks, Fred for your reply. I think I would prefer to work from one basic model of hammer preparation and the dense core, gradiant softening to surface model is a good one and plenty complex enough to work with, without me introducing extra variables. One reframed question to you, David, or anyone else who may have experience with this, does hardening from the staple down support this model, unnecessarily close off needling options that are useful, or just not make enough difference one way or the other?

And thanks, David, for offering us the upper right graph. It does seem to represent my hoped-for aspiration for hammer performance. One comment in your response intrigued me: "Applying drops of hardener to the strike point or shoulder only fails in concept." One pragmatic reading of this that I pretty much subscribe to might be: "What works, works - if something needs to happen, have an open mind as to the means, regardless of preconceptions". Yet we need a well-considered starting point / frame of reference. I think that you and Fred are describing a similar vision of what will lead most readily to the graphically-imagined result. But. What did you intend with that interesting, somewhat provocative inclusion?

CB

-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------






Original Message:
Sent: 03-18-2013 23:07
From: David Love
Subject: lacquer voicing

I'm reposting this in plain text as the previous post went in HTML and is a mess.

David Love
www.davidlovepianos.com

Christopher:

The reason to add lacquer to a hammer is simple really. It's to shape the curve of compression or density dynamics. Pure and simple. I have attached a set of graphs which will likely get filtered but if so I will try and repost them as “standard timing” graphs. They are a dynamic illustration of the non linear spring quality of hammer, or some hypotheticals anyway. The one on the top right (looks like the right side of a parabola—like the right side of a “U” with some greater horizontal displacement along the x-axis, not so vertical a line) illustrates what should happen as we increasingly go through the dynamic ladder from pianissimo to fortissimo. The hammer should become increasingly more dense. This accomplishes two important things: It allows a progressive dynamic continuum, each more forceful stroke produces a progressively louder tone, that progression should be smooth without peaks and valleys along the way. Also, the progressive density provides an ever increasing excitation of higher partials. As we play more forcefully, the tone should get progressively brighter, more complex, more stuff, bigger, broader, however you wish to view it.

The reason to add lacquer is to get the inner structure of the hammer to conform to that non-linear spring quality. Similarly, if the hammer is too rigid, or locked down, too stiff, inflexible, if we only voice on the crown of the hammer or harden the shoulders only, we won’t get that progressive effect. If the hammer doesn’t continue to resist us from say firming the shoulders only with lacquer and not between the crown and the molding, we will max out beneath our top level potential. If the hammer is too rigid we won’t get a progression and, ironically, that can also limit the upper end dynamic range. If the hammer is simply softened on the surface and not underneath to give some flexibility then the upward curve will be too steep, we will hit our fortissimo right after we push through pianissimo. Various shapes of curves indicate the type of dynamic line that can be drawn but clearly our goal is the one on the top right (I hope this comes through).

Lacquer simply provides the medium that helps to create this structural goal. Are there better materials to use? There might be. Keytop was a failure, too rigid. Other melted plastics such as plexiglass when applied for this purpose also fail for similar reasons. Applying drops of hardener to the strike point or shoulder only fails in concept. It’s certainly something to think about though. Is there a better material that provides the structural support that we need? I don’t know the answer to that, but it’s worth considering.


-------------------------------------------
Christopher Brown
Owner
TPR Tools
Littleton MA
978-486-0610
-------------------------------------------

Paul: Thanks for the input. In my opinion, this is a problem with the integrity of the hammer from the start. If they've dipped the hammer and it's still a cotton ball when you get it then in my view the hammer is defective, though they may argue that it falls within their realm of acceptability. Honestly, it is this type of experience that some years ago got me to simply reject the product when given a choice. It's unfortunate because now you own the problem. It's a year after the fact, though I think you should tell them, FWIW. The hammer is now sealed and it will be difficult to get further and adequate penetrations. Ideally they should refund your money or give you a new set. If they did for some reason, it's not clear that the new set won't have the same problems so I would advise asking for an undipped set if you continue to use these products, establish your own protocols. I wish I could comment on what to do about these but not knowing what the you have now in front of you I'm reluctant to make suggestions. You can contact me off list if you wish to discuss further. David Love www.davidlovepianos.com I don't often do hammer jobs, but I did a Steinway M a year ago. The hammers were hardly more than cotton balls, even though they were stock Steinway hammers which were pre-lacquered. I used some store-bought lacquer and put it just above the moldings, as you describe. It wasn't nearly enough, and subsequent attempts didn't do much. Especially since it takes time to harden, and makes awful fumes in the home! It might have been easier if I'd had the piano in my shop. I ended up using keytop solution, and now the voicing is uneven. Friggin' mess. So, again, I'm trying to undo what I've done to some extent and hope to learn from this discussion where to go next. Keep it comin' Paul McCloud San Diego

I'd like to comment on this subject, though it may seem immaterial at first, and possibly irrelevant to the subject at hand. But if you will bear with me, there is some correlation.

I once had to replace a set of dampers on a 9' (not actually 9' per se, but you know what I mean) Steinway concert grand.

It did not go as well as I hoped, that being, the dampers ordered directly from Steinway were not exactly cut true to form, and I actually had to use some dampers from traditional piano supply houses to finish the job at hand.

What I gleaned from this experience was this.

If when Steinway has a set of parts that do not measure up, they simply toss them and reach for another set from the shelf, ad infinitium.

When I, or a technician such as I, orders a set of parts from Steinway, you work with what you get. There is no shelf to go to start over.

In the future if I were to ever order parts from a prestigious company, I would order at a minimum three sets of the same parts, and then I would not have the problem I had from that particular set of inferior parts that I had originally received, but that is because I didn't know any better at the time.

Keith McGavern, RPT
Shawnee, Oklahoma, USA
tune-repair@allegiance.tv

Original Message:
Sent: 03-18-2013 23:51
From: David Love
... In my opinion, this is a problem with the integrity of the hammer from the start.  ...

Christopher: Sorry, there was some ambiguity owing to my choice of word order. When I read it later I realized it could be read two ways. "Applying drops of hardener to the strike point or shoulder only-- fails in concept." or "Applying drops of hardener to the strike point or shoulder-- only fails in concept." It's the first one that was the intended meaning. I believe that applying keytop or hardening agents only to the strike point or shoulders fails to create the dynamic response that we want out of the hammer. Applying directly to the strike point tends to create a hard cap on the hammer while underneath it remains softish. In the worst case this can create a reverse response with respect to partial development. When you play lightly you get high partial development but when you play louder the hard cap gets buried in the collapsing hammer (not properly reinforced) and the sound gets louder but duller, or with less high partial development or with a funny looking curve anyway. The dynamic curve that I posted as a target can also be applied to the development of upper partials. The more force we apply we hope for a greater range of partial development. Doing things this way can alter that. If the hammer is supported underneath, however, then sharpening the attack some (if that's where the hammer is weak, for example, from not allowing the material to wick close enough to the surface at the first application) might be what is needed. A local application there is with some risk, though. It's easy to overdo it and then have to needle it back which over the long term can compromise the strike point. If the material penetrates down and mingles with the already hardened area below you can create a hard spot that can only be addressed by going down after it. That can be hard to control. Keytop solution has its own problems but can be useful in concert situations when a quick remedy is needed. We probably should differentiate between heroic efforts that are used on concert instruments to tweak things quickly and our normal every day target. Concert instruments are somewhat unique for several reasons. They tend to be kept more on the edge of the envelope which makes them less stable. The requirements between concert artists can vary considerably (can you imagine having to prepare the same piano back to back for Horowitz and then Alfred Brendel :-O OMG!). Also, the demands of artists who can audioize (is that a word) thirty rows out as opposed to those that want it now and at the bench can alter the demands yet again. So in these situations we do what is necessary. But we should probably be cautious about using those situations as a general guideline. I prefer, therefore, to not apply hardeners directly to the crown in this manner. If a bit more shine is required I prefer to polish with very fine paper. If a solution needs to be used, the weakest solution possible and in the thinnest line (fine needled applicator) followed by judicious needling . But the specific situation will dictate and there are a lot of variables and outcomes. With respect to should firming, it's interesting. Some technicians report that this will boost the power, my experience has been generally that it doesn't. In a recent conversation with Nick Gravagne about this I expressed that I thought it was probably because the material wicks slowly under the strike point after you've left it and containing it only on the shoulder is probably not what actually happens. But after the conversation I was thinking about this some more and it occurred to me that something else might be at play. My experience has generally been that this application is useless. However, the hammers that I use, or order, tend to be lower profile, thinner felt over the molding. When the hammer impacts the string it obviously compresses. Some of the force is directed straight down but some is directed out toward the shoulders. My thought is that in a relatively high profile hammer the should can come into play before the hammer bottoms out, so to speak, against the molding directly beneath the strike point. In a low profile hammer the felt will compress against the molding before the shoulder comes into play. Thus, in a high profile hammer it may be that the reinforced shoulder becomes a factor while in the low profile hammer it doesn't. I don't know if that's the case or not as the exact dynamic response of the felt when compressed is something I don't have any data on, but it's a thought. It could also be as I indicated to Nick, that the lacquer actually gets under the strike point when you aren't looking, sneaky stuff. Whether or not that's the case it's still a poor substitute for hardening between the strike point and the molding where most of the force is directed, presumably. Firming the shoulders will not likely provide enough support to the hammer overall to keep it from hitting a plateau prematurely when pushing up the dynamic curve. Moreover, keeping the shoulder flexible when you will, eventually, have to firm up the area directly below the strike point, is an important consideration. It think firming the hammer way down by the staple or T-Pin is probably useless as I would be surprised if that area of the hammer comes into play in any such situation--notwithstanding the ability to release tension from that area in a tensioned hammer toward the crown, so called "battery voicing". But that's yet another topic for discussion. I do have some thoughts on that as well. Forgive the typos and grammatical errors, my editor (me) wants to go to lunch. David Love www.davidlovepianos.com
Original Message----- From: Christopher Brown [mailto:noreply@egroups.ptg.org] Sent: Tuesday, March 19, 2013 10:24 AM To: David Love Subject: Voicing: RE:lacquer voicing Thanks, Fred for your reply. I think I would prefer to work from one basic model of hammer preparation and the dense core, gradiant softening to surface model is a good one and plenty complex enough to work with, without me introducing extra variables. One reframed question to you, David, or anyone else who may have experience with this, does hardening from the staple down support this model, unnecessarily close off needling options that are useful, or just not make enough difference one way or the other? And thanks, David, for offering us the upper right graph. It does seem to represent my hoped-for aspiration for hammer performance. One comment in your response intrigued me: "Applying drops of hardener to the strike point or shoulder only fails in concept." One pragmatic reading of this that I pretty much subscribe to might be: "What works, works - if something needs to happen, have an open mind as to the means, regardless of preconceptions". Yet we need a well-considered starting point / frame of reference. I think that you and Fred are describing a similar vision of what will lead most readily to the graphically-imagined result. But. What did you intend with that interesting, somewhat provocative inclusion? CB ------------------------------------------- Christopher Brown Owner TPR Tools Littleton MA 978-486-0610 -------------------------------------------

I have seen one example of applying lacquer exclusively to the shoulders, and it wasn't a pretty sight.  It was a Baldwin D in a college concert hall.  The shoulders were like new, but the crowns, from 10:30 to 1:30, were chewed up and hollowed out - from the side, they looked like the cross section of a volcano.  Because the shoulders were so rigid, the crown felt was caught between a rock and a hard place, and quickly tore apart.
-------------------------------------------
Michael Spalding
Fredonia WI
262-692-3943
-------------------------------------------






Original Message:
Sent: 03-19-2013 15:27
From: David Love
Subject: lacquer voicing

Christopher:

Sorry, there was some ambiguity owing to my choice of word order. When I read it later I realized it could be read two ways.

"Applying drops of hardener to the strike point or shoulder only-- fails in concept." or

"Applying drops of hardener to the strike point or shoulder-- only fails in concept."

It's the first one that was the intended meaning. I believe that applying keytop or hardening agents only to the strike point or shoulders fails to create the dynamic response that we want out of the hammer.

Applying directly to the strike point tends to create a hard cap on the hammer while underneath it remains softish. In the worst case this can create a reverse response with respect to partial development. When you play lightly you get high partial development but when you play louder the hard cap gets buried in the collapsing hammer (not properly reinforced) and the sound gets louder but duller, or with less high partial development or with a funny looking curve anyway. The dynamic curve that I posted as a target can also be applied to the development of upper partials. The more force we apply we hope for a greater range of partial development. Doing things this way can alter that.

If the hammer is supported underneath, however, then sharpening the attack some (if that's where the hammer is weak, for example, from not allowing the material to wick close enough to the surface at the first application) might be what is needed. A local application there is with some risk, though. It's easy to overdo it and then have to needle it back which over the long term can compromise the strike point. If the material penetrates down and mingles with the already hardened area below you can create a hard spot that can only be addressed by going down after it. That can be hard to control. Keytop solution has its own problems but can be useful in concert situations when a quick remedy is needed.

We probably should differentiate between heroic efforts that are used on concert instruments to tweak things quickly and our normal every day target. Concert instruments are somewhat unique for several reasons. They tend to be kept more on the edge of the envelope which makes them less stable. The requirements between concert artists can vary considerably (can you imagine having to prepare the same piano back to back for Horowitz and then Alfred Brendel :-O OMG!). Also, the demands of artists who can audioize (is that a word) thirty rows out as opposed to those that want it now and at the bench can alter the demands yet again. So in these situations we do what is necessary. But we should probably be cautious about using those situations as a general guideline.

I prefer, therefore, to not apply hardeners directly to the crown in this manner. If a bit more shine is required I prefer to polish with very fine paper. If a solution needs to be used, the weakest solution possible and in the thinnest line (fine needled applicator) followed by judicious needling . But the specific situation will dictate and there are a lot of variables and outcomes.

With respect to should firming, it's interesting. Some technicians report that this will boost the power, my experience has been generally that it doesn't. In a recent conversation with Nick Gravagne about this I expressed that I thought it was probably because the material wicks slowly under the strike point after you've left it and containing it only on the shoulder is probably not what actually happens. But after the conversation I was thinking about this some more and it occurred to me that something else might be at play. My experience has generally been that this application is useless. However, the hammers that I use, or order, tend to be lower profile, thinner felt over the molding. When the hammer impacts the string it obviously compresses. Some of the force is directed straight down but some is directed out toward the shoulders. My thought is that in a relatively high profile hammer the should can come into play before the hammer bottoms out, so to speak, against the molding directly beneath the strike point. In a low profile hammer the felt will compress against the molding before the shoulder comes into play. Thus, in a high profile hammer it may be that the reinforced shoulder becomes a factor while in the low profile hammer it doesn't. I don't know if that's the case or not as the exact dynamic response of the felt when compressed is something I don't have any data on, but it's a thought. It could also be as I indicated to Nick, that the lacquer actually gets under the strike point when you aren't looking, sneaky stuff.

Whether or not that's the case it's still a poor substitute for hardening between the strike point and the molding where most of the force is directed, presumably. Firming the shoulders will not likely provide enough support to the hammer overall to keep it from hitting a plateau prematurely when pushing up the dynamic curve. Moreover, keeping the shoulder flexible when you will, eventually, have to firm up the area directly below the strike point, is an important consideration. It think firming the hammer way down by the staple or T-Pin is probably useless as I would be surprised if that area of the hammer comes into play in any such situation--notwithstanding the ability to release tension from that area in a tensioned hammer toward the crown, so called "battery voicing". But that's yet another topic for discussion. I do have some thoughts on that as well.

Forgive the typos and grammatical errors, my editor (me) wants to go to lunch.

David Love
www.davidlovepianos.com

There's no question that when you go from statics to dynamics things get very complicated and very fast. I'm certainly not an engineer by training and as I was telling Michael Spreeman recently, I know enough to get into trouble but not always enough to get out of it. But I do know where to go to when I get stuck on these engineering questions and thank you Del Fandrich and Nick Gravagne, especially, even if and when our goals differ. While it is complicated I think we can lose the forest for the trees, so to speak. There are some things we know about dynamic range and partial development as it relates to force, size and weight, various static hammer qualities, and the related effects of voicing (making the hammer more or less compliant). These things are illustrated pretty clearly in the Five Lectures on the Acoustics of the Piano and there is a growing body of research to confirm (or deny) what we think we hear. We also know pretty much what we want in the most basic sense. Our subject is neither to be a piano nor a forte, but a pianoforte. It needs to play soft as well as loud and in a progressive way (we don't want it getting softer as we apply more force, if that were even possible). We know that there are limits as to how loud and soft we can make it based on what has to happen structurally and what can happen to the quality of the sound when we try to push it too far, tax too heavily the resources of the resonant structure, or, for that matter, build the structure in such a way that we can't extract enough of what we want. We know that we want a variable rate of partial development and that it should relate to how much force we apply. We know that the piano literature calls for certain qualities and a ranges that need to be delivered. Often that full range of requirements falls in a single piece (certainly in a single program) such as a Schumann suite, or a Beethoven sonata, a Kapustin set of variations (my new favorite discovery) so the argument that certain pianos are meant for certain music falls short. While we can play with designs (both scale and soundboard) to target something in preference over something else (for example sustain over loudness, high partial development over fundamental) we can really only go so far before we move outside of that relatively small window of acceptability--when it becomes something other than what we need or expect or no longer functions effectively to capture the range of what the literature requires. So I don't think it's as daunting a task as you might be suggesting and I would caution about getting too hung up on the physical mysteries and explanations that we forget to respond to what we hear. That's usually a pretty good guide as to what is working and what isn't, better than the super slow motion video, or the fancy spread sheet or graph, when it comes right down to it. That's not to say that those things aren't important, they certainly are and can go a long way to further our understanding, help us with prescriptive solutions to problems, and identify more clearly what it is that we are hearing. But we will never have that visceral response to a graph that we do to the music itself that tells us whether it's right or not, well, most of us anyway. There are lots of questions to answer and there will always be more. But we shouldn't be paralyzed by that or let it prevent us from sticking our necks out and making an esthetic judgment. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Tuesday, March 19, 2013 11:53 AM To: David Love Subject: Voicing: RE:lacquer voicing One of the reasons any discussion of voicing is frustrating at best lies in the fact that we really don't understand anywhere near fully the interaction of the hammer and string, and exactly how that results in the tonal results we hear. The explanations we make are always incomplete and often at odds with the facts. Snip...

What I was trying to get at was not so much the impossibility of arriving at a complete understanding of the physics of hammer/string interaction, but more the likelihood that our mental models, our theoretical constructs, are in many ways apt to be at odds with the facts that we do know, when we look closely enough. For instance, a springy hammer may produce the best tonal results, but it is not because it "makes the hammer rebound off the string faster" or at least this is not true in a literal sense. The hammer does not "rebound off the string."

There is danger in relying on mental constructs, helpful as they may be. All mental constructs having to do with voicing should be treated with a certain degree of skepticism and not simply swallowed whole. I do think we know that in general a hammer with a hard area at the crown and soft, springy shoulders will produce the best tone, the best range of tones. Do we know exactly how that happens? Not really. None of the explanations I have heard hold up to the facts that I know about string/hammer interaction, however vivid and reasonable-sounding they may be.

That's my point. Voicing I can do fairly successfully. And I can spout off with the best on rationales behind my voicing techniques. But I recognize that my spouting is more of a mental aid than it is a reflection of verified fact. I wish it were otherwise, but it is not.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 16:58
From: David Love
Subject: lacquer voicing

There's no question that when you go from statics to dynamics things get very complicated and very fast. I'm certainly not an engineer by training and as I was telling Michael Spreeman recently, I know enough to get into trouble but not always enough to get out of it. But I do know where to go to when I get stuck on these engineering questions and thank you Del Fandrich and Nick Gravagne, especially, even if and when our goals differ.

While it is complicated I think we can lose the forest for the trees, so to speak. There are some things we know about dynamic range and partial development as it relates to force, size and weight, various static hammer qualities, and the related effects of voicing (making the hammer more or less compliant). These things are illustrated pretty clearly in the Five Lectures on the Acoustics of the Piano and there is a growing body of research to confirm (or deny) what we think we hear.

We also know pretty much what we want in the most basic sense. Our subject is neither to be a piano nor a forte, but a pianoforte. It needs to play soft as well as loud and in a progressive way (we don't want it getting softer as we apply more force, if that were even possible). We know that there are limits as to how loud and soft we can make it based on what has to happen structurally and what can happen to the quality of the sound when we try to push it too far, tax too heavily the resources of the resonant structure, or, for that matter, build the structure in such a way that we can't extract enough of what we want. We know that we want a variable rate of partial development and that it should relate to how much force we apply. We know that the piano literature calls for certain qualities and a ranges that need to be delivered. Often that full range of requirements falls in a single piece (certainly in a single program) such as a Schumann suite, or a Beethoven sonata, a Kapustin set of variations (my new favorite discovery) so the argument that certain pianos are meant for certain music falls short. While we can play with designs (both scale and soundboard) to target something in preference over something else (for example sustain over loudness, high partial development over fundamental) we can really only go so far before we move outside of that relatively small window of acceptability--when it becomes something other than what we need or expect or no longer functions effectively to capture the range of what the literature requires.

So I don't think it's as daunting a task as you might be suggesting and I would caution about getting too hung up on the physical mysteries and explanations that we forget to respond to what we hear. That's usually a pretty good guide as to what is working and what isn't, better than the super slow motion video, or the fancy spread sheet or graph, when it comes right down to it. That's not to say that those things aren't important, they certainly are and can go a long way to further our understanding, help us with prescriptive solutions to problems, and identify more clearly what it is that we are hearing. But we will never have that visceral response to a graph that we do to the music itself that tells us whether it's right or not, well, most of us anyway.

There are lots of questions to answer and there will always be more. But we shouldn't be paralyzed by that or let it prevent us from sticking our necks out and making an esthetic judgment.



David Love
www.davidlovepianos.com

Of course. But mental constructs are important as analogous ways of thinking about things. I think there are very helpful especially in voicing where having a way of visualizing what is going on as it relates to what you hearing can be extremely useful. We can limit ourselves by trying to be too literal. I do agree that if you get locked into attempts at a scientific explanation at the expense of listening you won't get very far. On the other hand, finding a way to visualize what is happening can help guide your listening too. I'm not sure what you mean by "the hammer does not rebound off the string". The hammer is flexible, it compresses and decompresses. The elastic deformation that occurs (hysteresis) does complicate it but if you drop one on the floor it bounces. There is a spring quality to it. It also strikes something that is flexible and the dynamics do get very complicated, more so than I can explain in real scientific terms. But I'm not sure what you mean. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Tuesday, March 19, 2013 2:50 PM To: David Love Subject: Voicing: RE:lacquer voicing What I was trying to get at was not so much the impossibility of arriving at a complete understanding of the physics of hammer/string interaction, but more the likelihood that our mental models, our theoretical constructs, are in many ways apt to be at odds with the facts that we do know, when we look closely enough. For instance, a springy hammer may produce the best tonal results, but it is not because it "makes the hammer rebound off the string faster" or at least this is not true in a literal sense. The hammer does not "rebound off the string." There is danger in relying on mental constructs, helpful as they may be. All mental constructs having to do with voicing should be treated with a certain degree of skepticism and not simply swallowed whole. I do think we know that in general a hammer with a hard area at the crown and soft, springy shoulders will produce the best tone, the best range of tones. Do we know exactly how that happens? Not really. None of the explanations I have heard hold up to the facts that I know about string/hammer interaction, however vivid and reasonable-sounding they may be. That's my point. Voicing I can do fairly successfully. And I can spout off with the best on rationales behind my voicing techniques. But I recognize that my spouting is more of a mental aid than it is a reflection of verified fact. I wish it were otherwise, but it is not. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

David,
For me the word "bounce" means one contact between the two bodies, not multiple contacts. To save effort, I'll quote myself, concerning the Kawai video Don Mannino shows (have you seen it?):

"For example, we like to think of the hammer having a "springiness" as the result of which it may "bounce off" the string faster or "dwell on" the string longer depending on the force of the blow. How do we resolve that mental image with the high-speed Kawai video Don Mannino often shows:

1 hammer strikes string;
2 string is impelled upward, leaving the hammer, while the hammer continues to rise;
3 string comes back down, meeting the hammer, and the hammer almost stops moving upward while the string again moves upward leaving the hammer;
4 string comes down and meets the hammer, stopping the upward motion of the hammer, and string again moves upward;
5 a final meeting of the string and hammer results in the hammer descending fairly rapidly."

To me, the evidence of that video demonstrates pretty clearly that hammers do not "simply bounce" off strings. If springiness of the hammer affects the interaction (I'm certain it does), it is not is making a single contact shorter. What is the difference caused by springiness? I am perfectly honest and say "I don't know." I can speculate for you if you like, but I don't know (and I don't think you do either).

Not knowing with certainty does not mean paralysis, or it shouldn't. We continue to speculate, and act on our speculations. We continue to have our inner picturings of reality, which guide our actions. We are simply less doctrinaire, less apt to interpret results based on our foregone conclusions, a little more humble. I agree with Socrates, that the wise man is one who knows what he doesn't know. Sometimes it seems that the more I learn the less I know, but really it is a matter of realizing that "It is always more complicated than that."

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 18:45
From: David Love
Subject: lacquer voicing

Of course. But mental constructs are important as analogous ways of thinking about things. I think there are very helpful especially in voicing where having a way of visualizing what is going on as it relates to what you hearing can be extremely useful. We can limit ourselves by trying to be too literal. I do agree that if you get locked into attempts at a scientific explanation at the expense of listening you won't get very far. On the other hand, finding a way to visualize what is happening can help guide your listening too.

I'm not sure what you mean by "the hammer does not rebound off the string". The hammer is flexible, it compresses and decompresses. The elastic deformation that occurs (hysteresis) does complicate it but if you drop one on the floor it bounces. There is a spring quality to it. It also strikes something that is flexible and the dynamics do get very complicated, more so than I can explain in real scientific terms. But I'm not sure what you mean.


David Love
www.davidlovepianos.com

Well, no one said these things were simple. I have not seen the Mannino film but have seen other super slow motion video of this interaction and they seem to concur. Some of the problem comes from the terminology we are using. I am not a physicist or an engineer but "bounce" is not exactly a scientific term. I think this might be called an "elastic collision" in physics, or something like that. In the case of hammer and piano string the two bodies colliding are both elastic (unlike, say bouncing a ball on the sidewalk). The dynamics have to be quite complicated. However, in spite of the fact that the hammer seems to hang in mid air or even rise some after the collision doesn't mean that the reason the hammer ultimately reverses direction (bounces) is not for some other reason, ultimately, than its collision with the string. I think the variability of hammer string contact time is a pretty well documented phenomenon and there are established formulas for that that take into account all kinds of variables. Whether or not the total string contact time is a function of a single contact or multiple contacts given the elastic properties of both objects I don't know. It appears from these videos that the total contact time may well be a function of multiple interactions. That certainly makes things very complicated indeed. The Five Lectures on the Acoustics of the Piano touches on this subject and addresses some problems related to this with respect to the lower treble in particular. I cite this lengthy quote from Harold Conklin that may be of interest: "An entirely different picture develops if the contact durations are related to the period time of the fundamental (the inverse of the fundamental frequency) of the corresponding note (see Fig. 8). Now it can be seen that the contact durations are short in the bass in comparison with the fundamental period, while the opposite situation prevails in the treble. The implication is that longer contact time in the treble damps the upper partials and shorter contact time in the bass doesn’t. Piano tone will be better if some of the upper partials in the bass are damped and fewer of the upper partials in the treble are. Note the contact time in the area of C6? Is that due to hammer weight in that section? A general theorem in string physics helps us to interpret these differences. The theorem tells us that string resonances with period times essentially shorter than the contact duration will be only weakly excited by the blow. The implication of this theorem for the sound quality of the piano is that the bass notes will be rich in partials compared to the treble notes. This is so, because in the bass the contact duration is only about 10 % of the fundamental period; it is not until the 10th partial that we reach a period time that is short in comparison with the contact duration. In the treble on the other hand, even the fundamental period is much too short to be optimally excited, and the situation for the higher partials becomes successively worse. An alternative design of the piano could be imagined, such that the string contact durations were a constant fraction of the fundamental period over the entire compass. This would demand a rescaling of the striking points, much heavier bass hammers than "normal," and also lighter treble hammers. However, the sound would probably be rated as second to the present design, being too muddy in the bass and too brilliant in the treble. In this case the customers are likely to have good acoustical reasons to reject the new design. But even in the case of smaller changes which would be welcomed by the manufacturer, the customers are notoriously hard to convince about the benefit of news. Tradition bears a strong power on music and musical instruments. Imagine a traditional piano concerto being played on anything but a black grand piano!" David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Tuesday, March 19, 2013 5:48 PM To: David Love Subject: Voicing: RE:lacquer voicing David, For me the word "bounce" means one contact between the two bodies, not multiple contacts. To save effort, I'll quote myself, concerning the Kawai video Don Mannino shows (have you seen it?): "For example, we like to think of the hammer having a "springiness" as the result of which it may "bounce off" the string faster or "dwell on" the string longer depending on the force of the blow. How do we resolve that mental image with the high-speed Kawai video Don Mannino often shows: 1 hammer strikes string; 2 string is impelled upward, leaving the hammer, while the hammer continues to rise; 3 string comes back down, meeting the hammer, and the hammer almost stops moving upward while the string again moves upward leaving the hammer; 4 string comes down and meets the hammer, stopping the upward motion of the hammer, and string again moves upward; 5 a final meeting of the string and hammer results in the hammer descending fairly rapidly." To me, the evidence of that video demonstrates pretty clearly that hammers do not "simply bounce" off strings. If springiness of the hammer affects the interaction (I'm certain it does), it is not is making a single contact shorter. What is the difference caused by springiness? I am perfectly honest and say "I don't know." I can speculate for you if you like, but I don't know (and I don't think you do either). Not knowing with certainty does not mean paralysis, or it shouldn't. We continue to speculate, and act on our speculations. We continue to have our inner picturings of reality, which guide our actions. We are simply less doctrinaire, less apt to interpret results based on our foregone conclusions, a little more humble. I agree with Socrates, that the wise man is one who knows what he doesn't know. Sometimes it seems that the more I learn the less I know, but really it is a matter of realizing that "It is always more complicated than that." ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

David,
Those various generalizations from the Five Lectures have colored our thinking for years. They seemed to have analyzed things pretty carefully, with the precise timing of the reflected wave from the agraffe or capo, "touching the hammer before it left the string," and similar data. But the data they were working from seem very dated to me today. They were using fairly crude measuring devises, with electronic circuits that recorded the (fairly) precise time of contact.

Super high speed videography didn't exist, and to the extent it did (not so super high speed) it was prohibitively expensive, to shoot and develop miles of film. Digital technology made that sort of high speed visual investigation much more affordable, and the results are far more precise than the electronic circuits they used - and one can analyze the data in much greater detail, going frame by frame and seeing precisely what happens and when.

I wonder what Conklin would have thought, had he known that what he considered "hammer contact time" was in fact a series of contacts. He speaks of damping of upper partials. That sounds simple enough. But by what mechanism? By what mechanism precisely are upper partials excited and damped, especially in the context of multiple interactions between hammer and string? His speculation is based on far from complete information, as, for that matter, is any speculation based simply on the Mannino  film (without follow up investigation of the effects of changing several variables).

Which of the contacts of hammer and string are with the reflected wave from the agraffe? (one assumes the first, but, then does that contact cause a secondary reflection back to the agraffe?) How does that contact impact the generation of partials? Question upon question arises, making the analysis in the Five Lectures seem almost quaint. I understand Stephen BIrkett has done a lot of research along these more precise lines, and keep hearing rumors that some kind of publication is imminent - but his job is such that piano investigations are a labor of love, secondary in his official capacity to "pure mathematics" and mathematical modeling. BTW, I notice he has taken down the videos of various piano videos he had posted for a few years.

Anyway, for me the complexity is both invigorating and humbling. I know that I don't really know a whole lot. Actually, what struck me most about the multiple interactions between hammer and string was the implications for hammer/string mating, precision of travel, and precision of balance of the hammer on the shank (alignment, "burning" angle). And experimentation along those lines showed very clearly that attention to those aspects of prep pay many-fold returns in the focus of tone. As for the "voicing mechanism," how particular hammer "set ups" might behave in that scenario, I am still trying to get my mind around it, so far without a whole lot of clarity. So I rely mostly on empiricism: what works, what doesn't, based on experience.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 21:41
From: David Love
Subject: lacquer voicing

Well, no one said these things were simple. I have not seen the Mannino film but have seen other super slow motion video of this interaction and they seem to concur.

Some of the problem comes from the terminology we are using. I am not a physicist or an engineer but "bounce" is not exactly a scientific term. I think this might be called an "elastic collision" in physics, or something like that. In the case of hammer and piano string the two bodies colliding are both elastic (unlike, say bouncing a ball on the sidewalk). The dynamics have to be quite complicated. However, in spite of the fact that the hammer seems to hang in mid air or even rise some after the collision doesn't mean that the reason the hammer ultimately reverses direction (bounces) is not for some other reason, ultimately, than its collision with the string.

I think the variability of hammer string contact time is a pretty well documented phenomenon and there are established formulas for that that take into account all kinds of variables. Whether or not the total string contact time is a function of a single contact or multiple contacts given the elastic properties of both objects I don't know. It appears from these videos that the total contact time may well be a function of multiple interactions. That certainly makes things very complicated indeed.

The Five Lectures on the Acoustics of the Piano touches on this subject and addresses some problems related to this with respect to the lower treble in particular.

I cite this lengthy quote from Harold Conklin that may be of interest:




"An entirely different picture develops if the contact durations are related to the period time of the fundamental (the inverse of the fundamental frequency) of the corresponding note (see Fig. 8). Now it can be seen that the contact durations are short in the bass in comparison with the fundamental period, while the opposite situation prevails in the treble. The implication is that longer contact time in the treble damps the upper partials and shorter contact time in the bass doesn’t. Piano tone will be better if some of the upper partials in the bass are damped and fewer of the upper partials in the treble are. Note the contact time in the area of C6? Is that due to hammer weight in that section?

A general theorem in string physics helps us to interpret these differences. The theorem tells us that string resonances with period times essentially shorter than the contact duration will be only weakly excited by the blow. The implication of this theorem for the sound quality of the piano is that the bass notes will be rich in partials compared to the treble notes. This is so, because in the bass the contact duration is only about 10 % of the fundamental period; it is not until the 10th partial that we reach a period time that is short in comparison with the contact duration. In the treble on the other hand, even the fundamental period is much too short to be optimally excited, and the situation for the higher partials becomes successively worse.

An alternative design of the piano could be imagined, such that the string contact durations were a constant fraction of the fundamental period over the entire compass. This would demand a rescaling of the striking points, much heavier bass hammers than "normal," and also lighter treble hammers. However, the sound would probably be rated as second to the present design, being too muddy in the bass and too brilliant in the treble.

In this case the customers are likely to have good acoustical reasons to reject the new design. But even in the case of smaller changes which would be welcomed by the manufacturer, the customers are notoriously hard to convince about the benefit of news. Tradition bears a strong power on music and musical instruments. Imagine a traditional piano concerto being played on anything but a black grand piano!"



David Love
www.davidlovepianos.com

I'm sure there are more sophisticated ways of measuring now and there will be even more to come, no doubt. I don't know for fact if the research of the five lectures holds up or not but as far as I know it does. The precise mechanics that describe how hammers interact with the strings, partials are excited or damped (we didn't even mention the shank flex or vertical alignment of the hammer at impact, yipes!) is important but that they are excited and damped and the general principles that govern that are probably more important for our purposes. That's why I don't get too bothered by the fact that there is always some greater depth of understanding. It's interesting, but we shouldn't be paralyzed by not knowing how things are happening at the subatomic level. The empirical evidence is pretty clear, put a heavy hammer on at C88 or a light one on at A0 and you can tell something different is happening, and it isn't all good. Clearly, a complete and total understanding of all this is extremely complicated, certainly beyond my expertise. But no matter how complicated it all is, when I step outside and stick my finger into the breeze, I don't think about my latitude, elevation, proximity to the ocean, mountain ranges, humidity, coriolis effect, ocean currents, or any other factors. Bottom line is this, as Bob Dylan said, "you don't need a weather man to know which way the wind blows". But it couldn't hurt. Good discussion. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Tuesday, March 19, 2013 8:07 PM To: David Love Subject: Voicing: RE:lacquer voicing David, Those various generalizations from the Five Lectures have colored our thinking for years. They seemed to have analyzed things pretty carefully, with the precise timing of the reflected wave from the agraffe or capo, "touching the hammer before it left the string," and similar data. But the data they were working from seem very dated to me today. They were using fairly crude measuring devises, with electronic circuits that recorded the (fairly) precise time of contact. Super high speed videography didn't exist, and to the extent it did (not so super high speed) it was prohibitively expensive, to shoot and develop miles of film. Digital technology made that sort of high speed visual investigation much more affordable, and the results are far more precise than the electronic circuits they used - and one can analyze the data in much greater detail, going frame by frame and seeing precisely what happens and when. I wonder what Conklin would have thought, had he known that what he considered "hammer contact time" was in fact a series of contacts. He speaks of damping of upper partials. That sounds simple enough. But by what mechanism? By what mechanism precisely are upper partials excited and damped, especially in the context of multiple interactions between hammer and string? His speculation is based on far from complete information, as, for that matter, is any speculation based simply on the Mannino film (without follow up investigation of the effects of changing several variables). Which of the contacts of hammer and string are with the reflected wave from the agraffe? (one assumes the first, but, then does that contact cause a secondary reflection back to the agraffe?) How does that contact impact the generation of partials? Question upon question arises, making the analysis in the Five Lectures seem almost quaint. I understand Stephen BIrkett has done a lot of research along these more precise lines, and keep hearing rumors that some kind of publication is imminent - but his job is such that piano investigations are a labor of love, secondary in his official capacity to "pure mathematics" and mathematical modeling. BTW, I notice he has taken down the videos of various piano videos he had posted for a few years. Anyway, for me the complexity is both invigorating and humbling. I know that I don't really know a whole lot. Actually, what struck me most about the multiple interactions between hammer and string was the implications for hammer/string mating, precision of travel, and precision of balance of the hammer on the shank (alignment, "burning" angle). And experimentation along those lines showed very clearly that attention to those aspects of prep pay many-fold returns in the focus of tone. As for the "voicing mechanism," how particular hammer "set ups" might behave in that scenario, I am still trying to get my mind around it, so far without a whole lot of clarity. So I rely mostly on empiricism: what works, what doesn't, based on experience. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

The complexity isn't at all paralyzing, and, in fact, I think it leads to a better practical understanding. For me, pondering those multiple contacts made me focus much more on "pre-voicing prep" as in the things I have kept writing about ad nauseum: travel/square/level strings/mate. In a multiple contact scenario, it seemed to me that any chaos in the system would cause inconsistent "voicing" because different things would be damped at different force levels. That would be unpredictable,  as minor changes in the force of a key stroke could create a different "vibration/shiver" in the hammer/shank (if it weren't precisely traveled and squared), for instance.

The more I have focused on those aspects, the more I have become convinced that this is true. Focus of tone is far better and very noticeably so. The tonal gradient rises nicely and evenly in all hammers if I do consistent needling or other work on them, no big "sticking out" hammers at unpredictable volume levels. "Zings" that I used to attribute to "front duplex noise" have ceased to be the major problem they once were for me.

And all this is amplified in the lacquer hammer, or, more precisely, the "hammer voiced to be brilliant." I think that the string/hammer interactions in a "chaotic set up" (lack of good travel/square/level/mate) create even more unpredictable voicing "gradients" (as in the sound produced by a hammer suddenly "stands out" at particular force levels), leading us to the intuitive approach of "needling out" that sound in an approach "customized to each hammer." And the results are frustrating and unsuccessful.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-19-2013 23:48
From: David Love
Subject: lacquer voicing

I'm sure there are more sophisticated ways of measuring now and there will be even more to come, no doubt. I don't know for fact if the research of the five lectures holds up or not but as far as I know it does. The precise mechanics that describe how hammers interact with the strings, partials are excited or damped (we didn't even mention the shank flex or vertical alignment of the hammer at impact, yipes!) is important but that they are excited and damped and the general principles that govern that are probably more important for our purposes. That's why I don't get too bothered by the fact that there is always some greater depth of understanding. It's interesting, but we shouldn't be paralyzed by not knowing how things are happening at the subatomic level. The empirical evidence is pretty clear, put a heavy hammer on at C88 or a light one on at A0 and you can tell something different is happening, and it isn't all good.

Clearly, a complete and total understanding of all this is extremely complicated, certainly beyond my expertise.

But no matter how complicated it all is, when I step outside and stick my finger into the breeze, I don't think about my latitude, elevation, proximity to the ocean, mountain ranges, humidity, coriolis effect, ocean currents, or any other factors. Bottom line is this, as Bob Dylan said, "you don't need a weather man to know which way the wind blows". But it couldn't hurt.

Good discussion.


David Love
www.davidlovepianos.com

Fred - Your comments about chaos in the system seem like a strong argument for replacing shanks with a controlled material such as WNG shanks - no?

And to talk to Christopher Brown about his regulation station to help insure consistent and precise vertical alignment! David Love www.davidlovepianos.com
Original Message----- From: Ben Ereddia [mailto:noreply@egroups.ptg.org] Sent: Wednesday, March 20, 2013 6:54 AM To: David Love Subject: Voicing: RE:lacquer voicing Fred - Your comments about chaos in the system seem like a strong argument for replacing shanks with a controlled material such as WNG shanks - no?

My point exactly. It should not be paralyzing. All the points you make are very valid and prevoicing processes, as you have often pointed out, are critical. Not sufficient by themselves but a critical foundation. I'm all for limiting chaos and unpredictability. The lacquered hammer presents its own unique problems but I think we are on the same page on that one in approach: both foundation and maintenance. I do prefer to avoid it when possible even though the substitutes can leave something to be desired as well. I'm working on that. Again, thanks for getting the topic going. Articulating helped me to clarify some of my own thoughts on the subject. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Wednesday, March 20, 2013 6:35 AM To: David Love Subject: Voicing: RE:lacquer voicing The complexity isn't at all paralyzing, and, in fact, I think it leads to a better practical understanding. For me, pondering those multiple contacts made me focus much more on "pre-voicing prep" as in the things I have kept writing about ad nauseum: travel/square/level strings/mate. In a multiple contact scenario, it seemed to me that any chaos in the system would cause inconsistent "voicing" because different things would be damped at different force levels. That would be unpredictable, as minor changes in the force of a key stroke could create a different "vibration/shiver" in the hammer/shank (if it weren't precisely traveled and squared), for instance. The more I have focused on those aspects, the more I have become convinced that this is true. Focus of tone is far better and very noticeably so. The tonal gradient rises nicely and evenly in all hammers if I do consistent needling or other work on them, no big "sticking out" hammers at unpredictable volume levels. "Zings" that I used to attribute to "front duplex noise" have ceased to be the major problem they once were for me. And all this is amplified in the lacquer hammer, or, more precisely, the "hammer voiced to be brilliant." I think that the string/hammer interactions in a "chaotic set up" (lack of good travel/square/level/mate) create even more unpredictable voicing "gradients" (as in the sound produced by a hammer suddenly "stands out" at particular force levels), leading us to the intuitive approach of "needling out" that sound in an approach "customized to each hammer." And the results are frustrating and unsuccessful. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

For some reasons a part of my remarks in this last post got lopped off, not sure whether it was a cut and paste problem or something else but let me add them back in here. While we may not have a complete understanding of the physics of hammer/string interaction (and let's not forget the soundboard contribution), we do know many things that should guide us in not only our voicing decisions but our hammer selection decisions as well. For example: We know that hammers can have a variety of static and dynamic properties and dimensions. We know that we have certain requirements in piano tone. We know that we must achieve a broad dynamic range both loud enough and soft enough. We know that the piano must progress through the dynamic range smoothly and at a constant rate We know that the piano string produces partials and the development of those partials is an important consideration in piano tone. We know that the balance of partials changes at different dynamic levels. We know that the partial balance changes as a function of weight and size of the hammer We know that the partial balance changes as a function of compliance (softness) in the hammer. We know that we can alter the compliance through voicing. We know that the various dimensions on which the hammer can function can operate at cross purposes when it comes to partial development in different parts of the piano (weight and density for example) We know that the sounding structure of the piano interacts with all of the above. And so on. Whether as piano technicians we can explain in real scientific terms the physical dynamics (and a video doesn't do that either, btw, it just gives us a better picture), we shouldn't let that prevent us from using what we know to make more informed decisions about both hammer selection and voicing. While there will always be an empirical element (discovering what works and what doesn't by trial and error), it should still be guided by general principles. Identifying those general principles is a necessary first step. David Love www.davidlovepianos.com
Original Message----- From: David Love [mailto:noreply@egroups.ptg.org] Sent: Tuesday, March 19, 2013 8:52 PM To: David Love Subject: Voicing : RE: lacquer voicing I'm sure there are more sophisticated ways of measuring now and there will be even more to come, no doubt. I don't know for fact if the research of the five lectures holds up or not but as far as I know it does. The precise mechanics that describe how hammers interact with the strings, partials are excited or damped (we didn't even mention the shank flex or vertical alignment of the hammer at impact, yipes!) is important but that they are excited and damped and the general principles that govern that are probably more important for our purposes. That's why I don't get too bothered by the fact that there is always some greater depth of understanding. It's interesting, but we shouldn't be paralyzed by not knowing how things are happening at the subatomic level. The empirical evidence is pretty clear, put a heavy hammer on at C88 or a light one on at A0 and you can tell something different is happening, and it isn't all good. Clearly, a complete and total understanding of all this is extremely complicated, certainly beyond my expertise. But no matter how complicated it all is, when I step outside and stick my finger into the breeze, I don't think about my latitude, elevation, proximity to the ocean, mountain ranges, humidity, coriolis effect, ocean currents, or any other factors. Bottom line is this, as Bob Dylan said, "you don't need a weather man to know which way the wind blows". But it couldn't hurt. Good discussion. David Love www.davidlovepianos.com

I think those principles David set out are excellent. I have no quarrel with them.

However, I do think there are dangers inherent in adopting certain mental images of what happens and how, and then applying those to the practical world without a healthy dose of skepticism and an open mind. One of those mental images is that of the springy hammer "getting away from the string faster." Another is the image that the mix of partials is principally influenced by how long the hammer "dwells on" the string, damping more upper partials the longer it dwells. Put them together, and the "springy" hammer gives the "brighter" sound with harder blows, because it gets off the string faster.

Both images seem to make sense, and on their basis lots of people who are treated as authorities give all sorts of advice, both as to selecting hammers and as to voicing procedures. But are the images true reflections of reality, and do they always lead to the best results?

Let's take the notion of "dwelling on the string," and for our purposes, say that that notion will include multiple interactions of hammer and string, as in the Kawai video. The mental model is that the faster the hammer gets away from the string, the more upper partials as part of the tonal mix. And the harder the blow, also the more upper partials will be part of the mix. Those two models are almost universally believed, or seem to be.

By analogy, a ball bounced with more force against a hard surface, comes back faster, and probably (as far as we know, we assume anyway) spends less time in contact with that surface. This would probably hold for a hammer against a string, if the string were rigid - and at the very top of the piano, it IS quite rigid. But in the center of the piano, the strings have a fair amount of give. Thus, as we see in the video, the hammer does not rebound directly from the string. Instead, the result of the impact is that the string moves away from the hammer, and the hammer isn't even stopped, but continues its upward movement. The string, constrained at its end and under tension, returns to meet the upward moving hammer, and that second impact still does not quite stop the hammer. The third impact pretty much stops the hammer, and the fourth is the the one that results in the hammer falling, both by gravity and "rebound."

All of this takes time, milliseconds, but measurable time. Suppose that we reduce the force of the same hammer. At some point (I speculate), that force will become low enough that there will be a single, simple interaction of hammer and string, and the hammer will rebound with only one actual touch. I speculate that this would mean less contact time than the example on the video. And I speculate that there is a continuum of different forces and different amounts of interaction time between hammer and string, in which at least some of the softer blows will have less contact time than the harder. And yet, of course, the softer blow will have less upper partials in the mix than the harder blow.

Of course, the fact is that we don't know what that curve of contact time would be, or even whether it would be a curve, without further experimental investigation. But it seems from the speculation I have inserted that the "dwelling/damping" model is far from a complete picture, and may not be the most important factor. It may be that the generation of upper partials is a more important factor than their suppression in creating a tone gradient, and it may be that their suppression has less to do with time than with some other factor taking place during contact(s).

Well, that has taken longer to get through than I had thought, so I'll leave it dangling and get to more of where I am heading with this in a later post.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-20-2013 10:08
From: David Love
Subject: lacquer voicing

For some reasons a part of my remarks in this last post got lopped off, not sure whether it was a cut and paste problem or something else but let me add them back in here.

While we may not have a complete understanding of the physics of hammer/string interaction (and let's not forget the soundboard contribution), we do know many things that should guide us in not only our voicing decisions but our hammer selection decisions as well. For example:

We know that hammers can have a variety of static and dynamic properties and dimensions.
We know that we have certain requirements in piano tone.
We know that we must achieve a broad dynamic range both loud enough and soft enough.
We know that the piano must progress through the dynamic range smoothly and at a constant rate
We know that the piano string produces partials and the development of those partials is an important consideration in piano tone.
We know that the balance of partials changes at different dynamic levels.
We know that the partial balance changes as a function of weight and size of the hammer
We know that the partial balance changes as a function of compliance (softness) in the hammer.
We know that we can alter the compliance through voicing.
We know that the various dimensions on which the hammer can function can operate at cross purposes when it comes to partial development in different parts of the piano (weight and density for example)
We know that the sounding structure of the piano interacts with all of the above.
And so on.

Whether as piano technicians we can explain in real scientific terms the physical dynamics (and a video doesn't do that either, btw, it just gives us a better picture), we shouldn't let that prevent us from using what we know to make more informed decisions about both hammer selection and voicing. While there will always be an empirical element (discovering what works and what doesn't by trial and error), it should still be guided by general principles. Identifying those general principles is a necessary first step.

David Love
www.davidlovepianos.com

Moving a little further down the path I was starting along in my last post:

Following the Five Lectures publication, a number of very intelligent and idealistic piano technicians started trying to apply many of the principles described in that book, as well as others they discovered or invented along the way, to come up with better ways to design or redesign pianos. There was a lot of discussion along those lines, on pianotech and elsewhere, principally about soundboard and hammer design, but other areas as well.

As a result of that discussion, with respect to hammers in particular, a philosophy was developed: to put it in its simplest terms, hammers should pressed without heat, and no hardeners should be used, as a result being more resilient, springier. There was and is a lot of argument backing up the reasons for this basic philosophy, much of it very persuasive, and much of it based on mental images formed as a result of Five Lectures. This philosophy was taken up by hammer makers, especially by Ronsen, and such hammers now became available to rebuilders. Over the years, many improvements were made to these hammers, and many rebuilders have had great success with them, particularly in pianos for private customers.

The philosophy of no heat and no hardeners has become a prevalent one among many, many influential people in the piano technician community, almost to the extent of being "quasi-religious belief" in character. I think we have all seen that over the past 20 years.

Then this style of hammer began to be used on some concert instruments (and let's allow Steinway D to stand in for concert instrument here), with less than stellar results: concert pianists rejected them as having no power, no brilliance. Piano technicians servicing them found they needed to apply lacquer to satisfy their customers.

The reaction of the "true believers" was one of shifting blame, and then of denial. Shifting blame to the piano design - that stupid compression crowning as opposed to the rational rib crown, that stupid duplex/aliquot system that robs power, etc. Well, pianos where those features were "fixed" through redesign also had considerable negative feedback.

So we come to denial: Those pianists don't know how to listen. They need to listen with their ears in the fifteenth row in the audience. They have been hearing the wrong tone for so long that they don't recognize truly beautiful tone when they hear it. I have read these claims in post after post and discussion after discussion. Hey, lots of luck telling the visiting concert pianist he needs to hear better, and that his tonal education sucks.

The plain fact is that the reason these hammers have been rejected (in this context) is their lack of ability, in the Steinway D in particular, to produce the brilliance required, to generate the high partials needed for such a performance instrument. I know there are lots of people whom this kind of statement will annoy, outrage, etc., but it is a plain fact: if you want to satisfy the concert hall customer, you need brilliance. And you can't get that brilliance in the Steinway D (or similar, heavy hammer design instrument) without either harder pressed hammers (with some heat used in all likelihood) or by adding lacquer. Or, shall we say, no cold-pressed hammer has yet been made, to my knowledge, that will produce the needed brilliance without hardener.

In my view, the mental image of the "perfect hammer" designed in accordance with mental images of how hammers and strings interact is responsible for this "cognitive dissonance" between what very well-intentioned, intelligent people believe to be true and what "actually works" on the ground. And part of the problem probably lies in understanding how exactly high partials are generated in strings: for the heavy hammer, it seems to require a pretty hard core to overcome any damping effects (if that is what is happening), as opposed to getting hammers off the string faster. Perhaps it has more to do with the way the hammer temporarily deforms the strings on impact. In any case, our mental image needs to be altered a bit to conform with "the facts on the streets." A model that works for lighter hammers does not seem to work for heavier ones.

I think I'll leave it there for now, and see what kind of response I get (don't need a flame suit, I'm burned up to a crisp already). But please note that I do not claim that cold pressed hammers are a bad idea, only that they do not seem to work for a Steinway D or similar instrument.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-21-2013 13:04
From: Fred Sturm
Subject: lacquer voicing

I think those principles David set out are excellent. I have no quarrel with them.

However, I do think there are dangers inherent in adopting certain mental images of what happens and how, and then applying those to the practical world without a healthy dose of skepticism and an open mind. One of those mental images is that of the springy hammer "getting away from the string faster." Another is the image that the mix of partials is principally influenced by how long the hammer "dwells on" the string, damping more upper partials the longer it dwells. Put them together, and the "springy" hammer gives the "brighter" sound with harder blows, because it gets off the string faster.

Both images seem to make sense, and on their basis lots of people who are treated as authorities give all sorts of advice, both as to selecting hammers and as to voicing procedures. But are the images true reflections of reality, and do they always lead to the best results?

Let's take the notion of "dwelling on the string," and for our purposes, say that that notion will include multiple interactions of hammer and string, as in the Kawai video. The mental model is that the faster the hammer gets away from the string, the more upper partials as part of the tonal mix. And the harder the blow, also the more upper partials will be part of the mix. Those two models are almost universally believed, or seem to be.

By analogy, a ball bounced with more force against a hard surface, comes back faster, and probably (as far as we know, we assume anyway) spends less time in contact with that surface. This would probably hold for a hammer bouncing against a string, if the string were rigid - and at the very top of the piano, it IS quite rigid. But in the center of the piano, the strings have a fair amount of give. Thus, as we see in the video, the hammer does not rebound directly from the string. Instead, the result of the impact is that the string moves away from the hammer, and the hammer isn't even stopped, but continues its upward movement. The string, constrained at its end and under tension, returns to meet the upward moving hammer, and that second impact still does not quite stop the hammer. The third impact pretty much stops the hammer, and the fourth is the the one that results in the hammer falling, both by gravity and "rebound."

All of this takes time, milliseconds, but measurable time. Suppose that we reduce the force of the same hammer. At some point (I speculate), that force will become low enough that there will be a single, simple interaction of hammer and string, and the hammer will rebound with only one actual touch. I speculate that this would mean less contact time than the example on the video. And I speculate that there is a continuum of different forces and different amounts of interaction time between hammer and string, in which at least some of the softer blows will have less contact time than the harder. And yet, of course, the softer blow will have less upper partials in the mix than the harder blow.

Of course, the fact is that we don't know what that curve of contact time would be, or even whether it would be a curve, without further experimental investigation. But it seems from the speculation I have inserted that the "dwelling/damping" model is far from a complete picture, and may not be the most important factor. It may be that the generation of upper partials is a more important factor than their suppression in creating a tone gradient, and it may be that their suppression has less to do with time than with some other factor taking place during contact(s).

Well, that has taken longer to get through than I had thought, so I'll leave it dangling and get to more of where I am heading with this in a later post.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------

Fred, Dave, et al,

Rumor is actually correct this time. A paper is very imminent - probably in the next issue of JASA (Journal of the Acoustical Society of America) - "Experimental investigation of the piano hammer-string interaction".

Someone touched on an important point and I'd like to emphasize this. There are 88 different hammer-string interactions and what goes on at A0 is completely different from C8. The multiple contacts you've seen in videos are interesting but actually not relevant for most of the notes. Things are also more complicated when the string length and other factors are such that the pulse has time to return from bridge to the hammer while it's still in contact with the string.

In the paper I took a single note (C4) and probed everything that I could measure or observe during the hammer-string interaction for a range of dynamic levels. It's a lot of stuff about just 2.5 ms. The compression of the felt, detailed motion of the strings and hammer, and flex of the shank, as well as measured forces during the contact are all reported. It might be an interesting read considering the various ideas that have been discussed here recently.

S

Thanks for that info. Is that an article that will be available on line? David Love www.davidlovepianos.com
Original Message----- From: Stephen Birkett [mailto:noreply@egroups.ptg.org] Sent: Thursday, March 21, 2013 6:36 PM To: David Love Subject: Voicing: RE:lacquer voicing Fred, Dave, et al, Rumor is actually correct this time. A paper is very imminent - probably in the next issue of JASA (Journal of the Acoustical Society of America) - "Experimental investigation of the piano hammer-string interaction". Someone touched on an important point and I'd like to emphasize this. There are 88 different hammer-string interactions and what goes on at A0 is completely different from C8. The multiple contacts you've seen in videos are interesting but actually not relevant for most of the notes. Things are also more complicated when the string length and other factors are such that the pulse has time to return from bridge to the hammer while it's still in contact with the string. In the paper I took a single note (C4) and probed everything that I could measure or observe during the hammer-string interaction for a range of dynamic levels. It's a lot of stuff about just 2.5 ms. The compression of the felt, detailed motion of the strings and hammer, and flex of the shank, as well as measured forces during the contact are all reported. It might be an interesting read considering the various ideas that have been discussed here recently. S

An interesting and imaginative perspective but completely wrong, and, it almost appears driven by some personal agenda directed at redesign people, who, btw (since I know many of them) are not driven by the "Five Lectures". The Five Lectures is simply a body of research that still has relevance. While it may be incomplete (as all research is) many of the findings they report hold up just fine in spite of your characterization of them as "quaint". I think that was the word you used. The issue of hammer cold pressing has nothing to do with soundboard design directions or even the specific requirements of any given piano. The two are completely independent of each other. That hammer design needs to be considered along with scale and soundboard is, at this point, common sense. Just as you wouldn’t but a massive Ronsen cold-pressed Bacon felt hammer on your Hamburg Steinway D, neither would you be advised to put a 22 lb Imadegawa hammer on a 1920 Steinway M with the original board somewhat compromised. Not unless you had some tonal goal that was far outside what I would consider to be even acceptable piano tone. BTW, the 1920 Steinway D had a cold pressed hammer. Very different dimensions than what we see now, but it was good enough for Rubenstein. The misuse of heat has specific implications for felt. That one is able to make the best of it is hardly an argument for advocating the excessive use of it. Modest amounts of heat are acceptable and may not do much damage but still are not without consequence. Talk to Jack Brand about felt and its qualities and sensitivities. I know of no better resource. It is clear that piano technicians can deal with even the worst of circumstances with respect to hammers, that doesn't mean we should embrace those as a goal. Hammer design and manufacturing cannot but summed up in a such a simplistic and biased viewpoint as you have offered. There are several parameters and dimensions that must be taken into account in the making of a hammer, all of them interacting (weight, tension, density, profile, pressing) and not the least of which is the quality of the hammer felt itself which dictates to a great degree those other dimensions and the manufacturing possibilities. The correct combination may be a balancing act, not perhaps achieved to your liking (or mine for that matter, at least not yet), but it doesn't preclude cold pressing. I can say that definitively from my own preliminary research and trials in this area. There have been many compensatory decisions made in hammer manufacturing driven, probably, by a number of factors: cost (perhaps mostly), bias, habit, appearance, misinformation, as well as to accommodate specific and idiosyncratic tonal goals, for instance, of many early Asian pianos. Those should not necessarily be viewed as the defining driving forces or characteristics of quality hammer construction. That you happen to judge all hammers by what must happen in a 3000 seat concert hall on a Steinway D or all redesign by one or two pianos that you may heard is a grossly limited view of the reality of what's actually taking place in the design arena. Moreover, your view that a cold pressed hammer cannot perform at the level that you seem to require is simply wrong. It may well be that the current iteration that you see from Ronsen, for example, is limited in this respect. But that doesn't mean that it's the only possible iteration or that "cold pressing" is even a defining property that carries with it built-in limitations. I think you need a bit more imagination, and certainly knowledge, of the possibilities that exist in hammer design and execution as well as the interaction between scale, soundboard and hammer. That hammer characteristics interact with scale and soundboard design is a simple fact and something that we experience every day. What do you imagine that voicing is primarily? Hammer mating? Why do we have to work hard to "open up" the Abel Natural on one piano and not on another? Do you think that's because of inherent manufacturing inconsistencies? Or is it because the impedance characteristics on any two given pianos are different and our voicing is, in reality, primarily a compensatory action designed to alter the hammer characteristics so that they match the specific needs of a particular piano. You would be correct if you chose the latter. Sorry, but you are grossly in error on this one. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Thursday, March 21, 2013 3:12 PM To: David Love Subject: Voicing: RE:lacquer voicing Moving a little further down the path I was starting along in my last post: Following the Five Lectures publication, a number of very intelligent and idealistic piano technicians started trying to apply many of the principles described in that book, as well as others they discovered or invented along the way, to come up with better ways to design or redesign pianos. There was a lot of discussion along those lines, on pianotech and elsewhere, principally about soundboard and hammer design, but other areas as well. As a result of that discussion, with respect to hammers in particular, a philosophy was developed: to put it in its simplest terms, hammers should pressed without heat, and no hardeners should be used, as a result being more resilient, springier. There was and is a lot of argument backing up the reasons for this basic philosophy, much of it very persuasive, and much of it based on mental images formed as a result of Five Lectures. This philosophy was taken up by hammer makers, especially by Ronsen, and such hammers now became available to rebuilders. Over the years, many improvements were made to these hammers, and many rebuilders have had great success with them, particularly in pianos for private customers. The philosophy of no heat and no hardeners has become a prevalent one among many, many influential people in the piano technician community, almost to the extent of being "quasi-religious belief" in character. I think we have all seen that over the past 20 years. Then this style of hammer began to be used on some concert instruments (and let's allow Steinway D to stand in for concert instrument here), with less than stellar results: concert pianists rejected them as having no power, no brilliance. Piano technicians servicing them found they needed to apply lacquer to satisfy their customers. The reaction of the "true believers" was one of shifting blame, and then of denial. Shifting blame to the piano design - that stupid compression crowning as opposed to the rational rib crown, that stupid duplex/aliquot system that robs power, etc. Well, pianos where those features were "fixed" through redesign also had considerable negative feedback. So we come to denial: Those pianists don't know how to listen. They need to listen with their ears in the fifteenth row in the audience. They have been hearing the wrong tone for so long that they don't recognize truly beautiful tone when they hear it. I have read these claims in post after post and discussion after discussion. Hey, lots of luck telling the visiting concert pianist he needs to hear better, and that his tonal education sucks. The plain fact is that the reason these hammers have been rejected (in this context) is their lack of ability, in the Steinway D in particular, to produce the brilliance required, to generate the high partials needed for such a performance instrument. I know there are lots of people whom this kind of statement will annoy, outrage, etc., but it is a plain fact: if you want to satisfy the concert hall customer, you need brilliance. And you can't get that brilliance in the Steinway D (or similar, heavy hammer design instrument) without either harder pressed hammers (with some heat used in all likelihood) or by adding lacquer. Or, shall we say, no cold-pressed hammer has yet been made, to my knowledge, that will produce the needed brilliance without hardener. In my view, the mental image of the "perfect hammer" designed in accordance with mental images of how hammers and strings interact is responsible for this "cognitive dissonance" between what very well-intentioned, intelligent people believe to be true and what "actually works" on the ground. And part of the problem probably lies in understanding how exactly high partials are generated in strings: for the heavy hammer, it seems to require a pretty hard core to overcome any damping effects (if that is what is happening), as opposed to getting hammers off the string faster. Perhaps it has more to do with the way the hammer temporarily deforms the strings on impact. In any case, our mental image needs to be altered a bit to conform with "the facts on the streets." A model that works for lighter hammers does not seem to work for heavier ones. I think I'll leave it there for now, and see what kind of response I get (don't need a flame suit, I'm burned up to a crisp already). But please note that I do not claim that cold pressed hammers are a bad idea, only that they do not seem to work for a Steinway D or similar instrument. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

Well, I probably shouldn't have gone down that road, as it seems to have distracted from the point I was trying to make rather than supporting it. All I was saying is that there is danger in being caught up with one's various mental images and the prejudices they engender. As a result, one's experiences may often become colored by one's expectations (with concomitant denial and various excuses), and also one may be less willing to do the things that actually work, less open to experimentation that doesn't follow the mental image one has already formed - the image becomes solidified, and there is less of an impulse to question.

The other point I was making, in my "speculations" about hammer-string interaction based on the Kawai video (which weren't entirely serious, BTW, merely examples of how a particular mental image of hammer string interaction might be questioned), is that we really know very little of the concrete details of this interaction, despite our ability (ably demonstrated in the post I am responding to) to weave very impressive arguments that bring in all sorts of variables.

This point is very well supported by Stephen Birkett's post, where, he says, "There are 88 different hammer-string interactions and what goes on at A0 is completely different from C8." And, in fact, I am sure he means that there are 88 different ranges of hammer-string interaction on any given piano (and with the hammers that are already in it, set up the way they are set up). It is far more complex than we imagine it, and all the theories we have spun over these many decades are based on a tiny glimpse of this complexity. In some ways, we might be better off simply following the "rule of thumb" guidance of piano and hammer manufacturers (where to stick the needles or apply the lacquer), amplified by our own experimental details, rather than trying to come up with a theory that will work to explain it - but that would be contrary to human nature.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-21-2013 23:36
From: David Love
Subject: lacquer voicing

An interesting and imaginative perspective but completely wrong, and, it almost appears driven by some personal agenda directed at redesign people, who, btw (since I know many of them) are not driven by the "Five Lectures". The Five Lectures is simply a body of research that still has relevance. While it may be incomplete (as all research is) many of the findings they report hold up just fine in spite of your characterization of them as "quaint". I think that was the word you used.

The issue of hammer cold pressing has nothing to do with soundboard design directions or even the specific requirements of any given piano. The two are completely independent of each other. That hammer design needs to be considered along with scale and soundboard is, at this point, common sense. Just as you wouldn’t but a massive Ronsen cold-pressed Bacon felt hammer on your Hamburg Steinway D, neither would you be advised to put a 22 lb Imadegawa hammer on a 1920 Steinway M with the original board somewhat compromised. Not unless you had some tonal goal that was far outside what I would consider to be even acceptable piano tone. BTW, the 1920 Steinway D had a cold pressed hammer. Very different dimensions than what we see now, but it was good enough for Rubenstein.

The misuse of heat has specific implications for felt. That one is able to make the best of it is hardly an argument for advocating the excessive use of it. Modest amounts of heat are acceptable and may not do much damage but still are not without consequence. Talk to Jack Brand about felt and its qualities and sensitivities. I know of no better resource. It is clear that piano technicians can deal with even the worst of circumstances with respect to hammers, that doesn't mean we should embrace those as a goal.

Hammer design and manufacturing cannot but summed up in a such a simplistic and biased viewpoint as you have offered. There are several parameters and dimensions that must be taken into account in the making of a hammer, all of them interacting (weight, tension, density, profile, pressing) and not the least of which is the quality of the hammer felt itself which dictates to a great degree those other dimensions and the manufacturing possibilities. The correct combination may be a balancing act, not perhaps achieved to your liking (or mine for that matter, at least not yet), but it doesn't preclude cold pressing. I can say that definitively from my own preliminary research and trials in this area.

There have been many compensatory decisions made in hammer manufacturing driven, probably, by a number of factors: cost (perhaps mostly), bias, habit, appearance, misinformation, as well as to accommodate specific and idiosyncratic tonal goals, for instance, of many early Asian pianos. Those should not necessarily be viewed as the defining driving forces or characteristics of quality hammer construction.

That you happen to judge all hammers by what must happen in a 3000 seat concert hall on a Steinway D or all redesign by one or two pianos that you may heard is a grossly limited view of the reality of what's actually taking place in the design arena. Moreover, your view that a cold pressed hammer cannot perform at the level that you seem to require is simply wrong. It may well be that the current iteration that you see from Ronsen, for example, is limited in this respect. But that doesn't mean that it's the only possible iteration or that "cold pressing" is even a defining property that carries with it built-in limitations.

I think you need a bit more imagination, and certainly knowledge, of the possibilities that exist in hammer design and execution as well as the interaction between scale, soundboard and hammer. That hammer characteristics interact with scale and soundboard design is a simple fact and something that we experience every day. What do you imagine that voicing is primarily? Hammer mating? Why do we have to work hard to "open up" the Abel Natural on one piano and not on another? Do you think that's because of inherent manufacturing inconsistencies? Or is it because the impedance characteristics on any two given pianos are different and our voicing is, in reality, primarily a compensatory action designed to alter the hammer characteristics so that they match the specific needs of a particular piano. You would be correct if you chose the latter.

Sorry, but you are grossly in error on this one.


David Love
www.davidlovepianos.com

Fred: I'm not exactly sure what you are saying here but let me just get right to the point. Hammers have certain attributes that influence how they act. Those attributes interact with each other. For my own purposes I have narrowed these down to five basic attributes. Those are: 1. Quality of the felt sheet itself (which dictates some of the other attributes) 2. Tension derived from the stretching of the felt in the hammer making process 3. Density 4. Hammer Profile (meaning the thickness of the felt over the molding 5. Weight In the design and execution of a hammer, those attributes must be balanced if you want the hammer to come out performing a certain way. Change the balance, you change the performance. Once you do that then you must rely on voicing (changing an attribute, such as density) in order to get the hammer back in balance and performing like you want. I don't see current hammer production doing that often enough, really getting the balance right or even paying attention to it, and so we often have to rely on extraordinary measures to get things to work. I do believe, btw, that the hammer can come out performing pretty much just as we want without jumping through voicing hoops. But in this respect, the fundamental approach to voicing should be structural, rather than procedural. You try and identify the specific attribute that needs to be changed and then you change it in order to rebalance the hammer. The attribute that needs to be changed and in which direction will determine the procedure. It may be any of the above (of course quality of felt is hard to change after the fact). If it's a weight issue you add or subtract, if it’s a profile issue, you file, density you needle or lacquer (if you must). But maybe it's two attributes. Maybe you need to both reduce profile and weight and maybe only in one section. Maybe you need to reduce profile and increase weight in another--life can be complicated. If you choose the wrong attribute then you will not achieve what you want and may, in fact, make things more difficult because now you have to correct your first mistake. There are many such choices that have to be made both at the manufacturing level and at the voicing level. All of these impact our two primary goals in piano tone and can be stated in the most simple terms as: that the piano should be able to play soft and loud in a graduated and controlled continuum, and that it should produce a predictable level of partials with a certain balance in each section of the piano. We always keep in mind that the piano's impedance characteristics influence how we set up those attributes and how they are balanced. And we also operate knowing that specific requirements (at least sectional requirements) through the scale will vary (i.e., we don't make all the hammers the same size, weight, density, etc.). My approach is, therefore, first to get all the attributes right in the first place. Second, when voicing is required to approach it structurally first and determine what needs to be changed. Then identify procedures that are required to do that. Yes, it is a mental construct, and a good one in my opinion: First identify the problem, then try and solve it. This is what I tried to teach at WestPacIII with respect to both choosing hammers (choosing hammer attributes really) and voicing which I think are inseparable. Of course, looking back at it now I would have changed my approach some and also made it a two period class with the discussion of hammer attributes flowing directly into principles of voicing. Hopefully, next time I'll be able to do that. For now, I think I've exhausted my input on this subject at least in this forum. I hope to produce a longer cohesive expository piece with more detailed discussion later, I'm working on that now. From what you have written it sounds like you are content with the status quo of what is being produced and just working with it the best you can trusting that our skill set will see us through. It probably will, it certainly has so far, well, except when it hasn't and the problems inherent in the hammer itself are beyond ours or anyone else's skill to achieve what we really want. But I seek a somewhat different approach. One in which the cohesive design of the hammer is much more targeted. We may have to leave our differences at that. I look at it this way, if you feel that the attention to detail that you put in the prevoicing process yields such positive results (something I agree with by the way), how could you not think that the same attention to detail in the hammer manufacturing process would yield even more profound results. To me it only makes sense and judging from what I hear all too frequently, there's some work to be done there. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Friday, March 22, 2013 1:44 PM To: David Love Subject: Voicing: RE:lacquer voicing Well, I probably shouldn't have gone down that road, as it seems to have distracted from the point I was trying to make rather than supporting it. All I was saying is that there is danger in being caught up with one's various mental images and the prejudices they engender. As a result, one's experiences may often become colored by one's expectations (with concomitant denial and various excuses), and also one may be less willing to do the things that actually work, less open to experimentation that doesn't follow the mental image one has already formed - the image becomes solidified, and there is less of an impulse to question. The other point I was making, in my "speculations" about hammer-string interaction based on the Kawai video (which weren't entirely serious, BTW, merely examples of how a particular mental image of hammer string interaction might be questioned), is that we really know very little of the concrete details of this interaction, despite our ability (ably demonstrated in the post I am responding to) to weave very impressive arguments that bring in all sorts of variables. This point is very well supported by Stephen Birkett's post, where, he says, "There are 88 different hammer-string interactions and what goes on at A0 is completely different from C8." And, in fact, I am sure he means that there are 88 different ranges of hammer-string interaction on any given piano (and with the hammers that are already in it, set up the way they are set up). It is far more complex than we imagine it, and all the theories we have spun over these many decades are based on a tiny glimpse of this complexity. In some ways, we might be better off simply following the "rule of thumb" guidance of piano and hammer manufacturers (where to stick the needles or apply the lacquer), amplified by our own experimental details, rather than trying to come up with a theory that will work to explain it - but that would be contrary to human nature. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

Hi David,
I agree with most of what you say in this post I am responding to. The differences between us are somewhat minor in a practical way, maybe more significant in a philosophical way.

For example, I am pretty well convinced through experience that every hammer needs some prepping to get the best tone quality, and I have strong doubts that this will change - although certainly I do welcome the efforts of hammer manufacturers to make this prep work less onerous. I believe (not dogmatically, but simply from long and varied observation, together with "reasoning") that a hammer out of the press needs to be "worked" in a way similar to how a pair of stiff jeans needs to be broken in (not strictly analogous, but somewhat so: both need to be "loosened up" from a static, stiff state). So I have no philosophical underpinning that says this sort of prep "shouldn't be necessary" and ought to be avoided if possible.

Furthermore, with respect to concert instruments as the extreme, but performance instruments in general (which include professional pianists' personal instruments, teachers' instruments, etc, etc), it seems clear to me, again from experience, that they require a fairly dense or stiff core, and that that is only achievable from either adding hardener to a softer press, or by harder pressing, which means quite a bit of shoulder work. And again, I have no philosophical underpinning saying either of those things "shouldn't be necessary" and ought to be avoided.

By all means, if a perfect hammer out of the box can be designed, I'm all for it, but I won't hold my breath.

All this said, I agree wholeheartedly that hammer work, whether hardening or needling, should be minimized for best results, and there we are pretty much in complete agreement. Steinway, for instance, has what I consider to be very inefficient techniques for hammer prepping, both NY and Hamburg. It is far more elegant, and gets better results, to minimize use of lacquer in the former, and to use the needles very sparingly, just as needed. They use too much hardener and their needle technique is too disorganized, so they go back and forth from needle to hardener and often end up with a mess (especially where a number of technicians have followed one another).

Hamburg hammers per se, as I mentioned earlier, I am not specifically very familiar with, but they seem to be overkill in terms of density, and the 50 - 75 strokes per shoulder for pre-voicing is overkill to my way of thinking (maybe it is necessary for that hammer, I don't know). I think, for instance, of the tone available from the Renner Blue Points Michael Spreeman puts in his pianos, with only an average 7 - 8 strokes per shoulder (deep ones), and it is exquisite.

With respect to use of heat in hammer making, again, I am a pragmatist: heat is used in the making of felt, steam heat is absolutely essential to the felting process. Heat is needed to iron wool pants to get out the wrinkles - try ironing with a setting that is below the boiling point - and the same is true for ironing key bushings. So to me it simply makes sense that some degree of heat would be used in pressing hammers. Obviously it needs to be controlled, and there are nasty examples out there of hammers that were made with too much heat and too much pressure. But the philosophy of purist "cold" pressing with zero heat doesn't make any sense to me. If it works, and produces hammers that are superior to all others for all applications, well and good. If it produces hammers that are better for certain applications and not for others, well and good. I think the latter is true, not the former, and I see no reason to lament the fact that heat is necessary to produce hammers for concert instruments and their like.

I guess one of our major differences in viewpoint rises from the fact that I am not involved in design/re-design, but almost always in simply making the best of what is in front of me. So I take more of an empirical approach.

In any case, I do hope that this exchange of various ideas and approaches is helpful and thought-provoking, and leads to a better understanding of this crucial topic. I know it has helped me get thoughts in order, altered a few perspectives, and provided some suggestions for moving forward.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-24-2013 04:18
From: David Love
Subject: lacquer voicing

Fred:

I'm not exactly sure what you are saying here but let me just get right to the point.

Hammers have certain attributes that influence how they act. Those attributes interact with each other.

For my own purposes I have narrowed these down to five basic attributes. Those are:

1. Quality of the felt sheet itself (which dictates some of the other attributes)
2. Tension derived from the stretching of the felt in the hammer making process
3. Density
4. Hammer Profile (meaning the thickness of the felt over the molding
5. Weight

In the design and execution of a hammer, those attributes must be balanced if you want the hammer to come out performing a certain way. Change the balance, you change the performance. Once you do that then you must rely on voicing (changing an attribute, such as density) in order to get the hammer back in balance and performing like you want. I don't see current hammer production doing that often enough, really getting the balance right or even paying attention to it, and so we often have to rely on extraordinary measures to get things to work. I do believe, btw, that the hammer can come out performing pretty much just as we want without jumping through voicing hoops.

But in this respect, the fundamental approach to voicing should be structural, rather than procedural. You try and identify the specific attribute that needs to be changed and then you change it in order to rebalance the hammer. The attribute that needs to be changed and in which direction will determine the procedure. It may be any of the above (of course quality of felt is hard to change after the fact). If it's a weight issue you add or subtract, if it’s a profile issue, you file, density you needle or lacquer (if you must). But maybe it's two attributes. Maybe you need to both reduce profile and weight and maybe only in one section. Maybe you need to reduce profile and increase weight in another--life can be complicated. If you choose the wrong attribute then you will not achieve what you want and may, in fact, make things more difficult because now you have to correct your first mistake.

There are many such choices that have to be made both at the manufacturing level and at the voicing level. All of these impact our two primary goals in piano tone and can be stated in the most simple terms as: that the piano should be able to play soft and loud in a graduated and controlled continuum, and that it should produce a predictable level of partials with a certain balance in each section of the piano.

We always keep in mind that the piano's impedance characteristics influence how we set up those attributes and how they are balanced. And we also operate knowing that specific requirements (at least sectional requirements) through the scale will vary (i.e., we don't make all the hammers the same size, weight, density, etc.).

My approach is, therefore, first to get all the attributes right in the first place. Second, when voicing is required to approach it structurally first and determine what needs to be changed. Then identify procedures that are required to do that. Yes, it is a mental construct, and a good one in my opinion: First identify the problem, then try and solve it.

This is what I tried to teach at WestPacIII with respect to both choosing hammers (choosing hammer attributes really) and voicing which I think are inseparable. Of course, looking back at it now I would have changed my approach some and also made it a two period class with the discussion of hammer attributes flowing directly into principles of voicing. Hopefully, next time I'll be able to do that.

For now, I think I've exhausted my input on this subject at least in this forum. I hope to produce a longer cohesive expository piece with more detailed discussion later, I'm working on that now. From what you have written it sounds like you are content with the status quo of what is being produced and just working with it the best you can trusting that our skill set will see us through. It probably will, it certainly has so far, well, except when it hasn't and the problems inherent in the hammer itself are beyond ours or anyone else's skill to achieve what we really want. But I seek a somewhat different approach. One in which the cohesive design of the hammer is much more targeted. We may have to leave our differences at that.

I look at it this way, if you feel that the attention to detail that you put in the prevoicing process yields such positive results (something I agree with by the way), how could you not think that the same attention to detail in the hammer manufacturing process would yield even more profound results. To me it only makes sense and judging from what I hear all too frequently, there's some work to be done there.

David Love
www.davidlovepianos.com

"Shouldn't be necessary", or "should be avoided" is probably an overstatement of my position. Minimized is a better way to put it. There will always be some work to do even if it's just balancing and smoothing within a given instrument. However, I think we can get much closer out of the box than we do currently if we choose correctly, or as I am suggesting, tailor the hammer attributes to the specific instrument, its impedance characteristics, and, of course, the tonal goal or model that you are trying to achieve. I do think that voicing procedures (needling, lacquer, and any other's you wish to mention) are destructive to the structural integrity of the hammer. Some more, some less but you cannot employ any procedure with total impunity. In one sense we probably agree with respect to concert instruments. Their requirements owning to both the high impedance characteristics plus the somewhat unusual requirements of a 30-rows-out baseline ratchets things up a bit, sometimes a lot. Michael Spreeman's pianos, from what I gather, a 220cm and a 270cm (if I got that right) are both, relatively speaking, higher tension scales (as you would expect with those sizes) with soundboards designed to function in sync with those scales. Even so, The Voicing the Renner Blue Point demo that I saw in Seattle left the piano somewhat overly bright as reported by the pianist who road tested it after the class was done. There was more work to be done there and more work had been done than 7-8 strokes in the shoulder, at least from my observation. In fairness, I can't say that that was a definitive demonstration for that hammer. But I would guess before the Blue Point Michael used something with somewhat similar attributes. BTW and FWIW, I don't consider 7-8 strokes in the shoulder to be excessive, 50 is though. But put that same hammer on a very low tension, lightweight soundboard, a 1920 Steinway M, original board with much lower impedance characteristics than the Ravenscroft 270, and you will certainly find that there is much more work to do. Enough so that maybe a hammer designed somewhat differently to begin with would have been a better fit. With respect to heat, we need to separate heat used in the fulling process of felt manufacturing from heat used in the making of hammer heads. They serve two distinctly different purposes. Any heat used in the hammer making process will impact tension. Excessive heat can destroy it completely. Now if you believe that tension is unimportant then that is another discussion and a worthwhile one for additional research. Hysteresis may well be the issue with respect to tension: how the spring-like quality of the hammer reacts during impact as opposed to following impact, the hammer's ability to recover its shape completely and at what rate after our elastic collision, implications for stability, and tonal implications as well. There are some articles that I've read that start to touch on this subject and it's very interesting, though I can't say I know the significance of it all at this point. It's further complicated because "tensioned" doesn't precisely describe the nature of the hammer. The hammer is tensioned on the outside layers but compressed on the inside (near the core molding). There exists in objects like this what is called a neutral axis--a place some distance below the surface where the hammer is neither under tension nor compression but neutral, where it transitions from tension to compression, as it were. That's probably a dynamic axis, meaning it changes or moves, maybe as we file the hammer and/or as we needle, maybe as it's played and stressed under a series of collisions. All very interesting in explaining, perhaps, why hammers that you needle seem to initially get less "bright" but grow increasingly more bright when just left alone over the first day or two. The release of tension on the outside may move the neutral axis outward and effectively add tension back or increase the density of the outer layers. There are many other possible implications as well but it's beyond this writing certainly, and probably left to the research scientists, of which, I am not one. But it does appear to me, from my own experience (and I have to rely on a symptomatic diagnoses lacking any good genetic markers or lab pathology reports) that hammers with a lot of tension have a somewhat different sound than hammers with no tension (or limited amounts of tension really--though there are some that seem to have none). They react differently to voicing protocols and have different levels of stability. Perhaps it's my imagination, but I don't think so. So far, I can't think of a reason why you wouldn't want to maximize tension in the hammer, especially as it impacts the hammer's ability to function in a spring-like manner. The cold pressing process seems to be the best way to do that. Quality felt is a necessary precursor and equally important in that it allows for adequate stretching (the manner in which tension is created). Other dimensional factors may play into this as well. The idea that cold pressing means that the hammer will lack power is to ignore the other hammer attributes that I mentioned now several times in previous posts that can impact the upper end of power. When I speak of it that way I am really referring to the amount of energy absorbed by the hammer that will not get to the string/soundboard assembly. The F = MA equation does not differentiate between a cold-pressed hammer and a hot-pressed hammer. The question of power delivered becomes, then, not one of the amount of force, but how much energy does the hammer itself absorb making it unavailable to the soundboard system. That is, after all, what we do when we "voice a piano down". By making the hammer more compliant it absorbs more energy and dissipates it in some other form than acoustic energy. So the question becomes can the amount of energy that is absorbed and dissipated by the hammer itself be minimized when necessary even with the cold pressing process thus achieving the power that we need without compromising, or with a minimal compromise, of tension. I think it can. But the entire spectrum of hammer attributes must be considered together. At least that is my current thinking. Just a quick comment on the design/redesign thing. Whether you like it or not you are involved with piano design. The things that you have to do to pianos are a function of their design (and execution). How design contributes to performance is important even if you aren't designing pianos from the ground up. The more we know about the effects of design the better off we are. But if by your comment you are suggesting that I am somehow coming to these conclusions based on my own interest in "redesigning" pianos, you are mistaken. While I do have experience in the "redesign arena", enough, to have informed and first hand experiences about what can happen, I am not driven by redesign in this hammer issue. My current projects, in fact, employ only very modest (if any) redesign features. My targets in this discussion are conventional pianos generally but may also include so-called redesigned pianos. Designs that really do push the tonal envelope may very well require something in terms of a specific combination of hammer attributes that is different from more conventional designs or approaches. But you can't lump them all together. The design elements between any two pianos, even conventional ones, will have inevitable overlaps and points where they diverge. Those similarities and differences cannot but summed up by the simple term "redesign". Well this went on far longer than I intended. Time to check in on Tiger Woods. Talk about redesign! David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Sunday, March 24, 2013 2:47 PM To: David Love Subject: Voicing: RE:lacquer voicing Hi David, I agree with most of what you say in this post I am responding to. The differences between us are somewhat minor in a practical way, maybe more significant in a philosophical way. For example, I am pretty well convinced through experience that every hammer needs some prepping to get the best tone quality, and I have strong doubts that this will change - although certainly I do welcome the efforts of hammer manufacturers to make this prep work less onerous. I believe (not dogmatically, but simply from long and varied observation, together with "reasoning") that a hammer out of the press needs to be "worked" in a way similar to how a pair of stiff jeans needs to be broken in (not strictly analogous, but somewhat so: both need to be "loosened up" from a static, stiff state). So I have no philosophical underpinning that says this sort of prep "shouldn't be necessary" and ought to be avoided if possible. Furthermore, with respect to concert instruments as the extreme, but performance instruments in general (which include professional pianists' personal instruments, teachers' instruments, etc, etc), it seems clear to me, again from experience, that they require a fairly dense or stiff core, and that that is only achievable from either adding hardener to a softer press, or by harder pressing, which means quite a bit of shoulder work. And again, I have no philosophical underpinning saying either of those things "shouldn't be necessary" and ought to be avoided. By all means, if a perfect hammer out of the box can be designed, I'm all for it, but I won't hold my breath. All this said, I agree wholeheartedly that hammer work, whether hardening or needling, should be minimized for best results, and there we are pretty much in complete agreement. Steinway, for instance, has what I consider to be very inefficient techniques for hammer prepping, both NY and Hamburg. It is far more elegant, and gets better results, to minimize use of lacquer in the former, and to use the needles very sparingly, just as needed. They use too much hardener and their needle technique is too disorganized, so they go back and forth from needle to hardener and often end up with a mess (especially where a number of technicians have followed one another). Hamburg hammers per se, as I mentioned earlier, I am not specifically very familiar with, but they seem to be overkill in terms of density, and the 50 - 75 strokes per shoulder for pre-voicing is overkill to my way of thinking (maybe it is necessary for that hammer, I don't know). I think, for instance, of the tone available from the Renner Blue Points Michael Spreeman puts in his pianos, with only an average 7 - 8 strokes per shoulder (deep ones), and it is exquisite. With respect to use of heat in hammer making, again, I am a pragmatist: heat is used in the making of felt, steam heat is absolutely essential to the felting process. Heat is needed to iron wool pants to get out the wrinkles - try ironing with a setting that is below the boiling point - and the same is true for ironing key bushings. So to me it simply makes sense that some degree of heat would be used in pressing hammers. Obviously it needs to be controlled, and there are nasty examples out there of hammers that were made with too much heat and too much pressure. But the philosophy of purist "cold" pressing with zero heat doesn't make any sense to me. If it works, and produces hammers that are superior to all others for all applications, well and good. If it produces hammers that are better for certain applications and not for others, well and good. I think the latter is true, not the former, and I see no reason to lament the fact that heat is necessary to produce hammers for concert instruments and their like. I guess one of our major differences in viewpoint rises from the fact that I am not involved in design/re-design, but almost always in simply making the best of what is in front of me. So I take more of an empirical approach. In any case, I do hope that this exchange of various ideas and approaches is helpful and thought-provoking, and leads to a better understanding of this crucial topic. I know it has helped me get thoughts in order, altered a few perspectives, and provided some suggestions for moving forward. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

David,
Thanks for a great, detailed post. I think most of it is spot on. The one, rather basic, point that I would take issue is
"Any heat used in the hammer making process will impact tension."
I guess we might need to define just what we mean by tension, as it functions within the structure of the hammer, and that becomes partly a matter of speculation (as in what you described as the area where tension and compression cross - a good conceptualization, and your thoughts about the shifting of compression and tension as a result of the needling process were spot on IMO).

I start from the premise that there is a certain amount of heat that will not, for our purposes, cause harm to the fibers themselves. For those who are purists, and say that any heat harms wool fibers, I would simply point out that felt hammers would be impossible without steam, which is hotter than boiling point, and that that amount of heat has to be acceptable, period. You can felt without that much heat, but not to the density needed for piano hammers.

Now suppose we start with a given felt strip, and press two sets of hammers using it, with every variable precisely the same except that in one case we will apply some moderate heat, within the limits used in fulling processes, and the other will be cold. What will be the difference in the hammer sets? I haven't done the experiment, but I believe from all sorts of analogous experiences and from what I have read, that it is likely the differences would be fairly minimal. Do you have any evidence that this is not the case?

What effect does heat have in the pressing process? On the molecular level, it makes the proteins in the fibers more compliant, less springy, while the heat is present, so that they are less resistant to being stretched or compressed. The individual fibers, millions of them, are acting together, but on an individual basis it has to do with the crimp, the curl of the fiber, and how much it is being stretched straight or bent. Together, these millions of interlocked fibers are being stretched and compressed, some one and some the other, some being pulled more straight while others, by accident of how they are aligned are being bent. If we simply heat and compress, then release, a certain amount of compression will be retained, but the material will not have been "felted" into that extra compression, and the compression will reverse with time or a certain amount of "working" or application of steam.

If you add heat to the whole mass, it is possible to stretch and compress the whole mass quite a bit more with the same amount of pressure, so you can fit more felt into the same space in the cauls and press the whole into what will be a tighter and more compressed mass. Fixing the ends by glue and staples to the molding that maintains the tension that holds the compression in a more or less static state. Heat allows pressing to a more compressed state than would be possible with cold pressing, because the felt cannot be stretched or compressed as much without that heat. The tension can be brought to a higher level with heat, resulting in more compression - though where the "boundary between the two" lies may be different from in a less densely pressed hammer, to the extent that it is hard to discern the tension because the compression is more noticeable (but that compression couldn't be there without the presence of the tension).

So it is really the choice of how much additional pressure (whether by cramming more felt in, starting with denser felt, or other variables) that determines the major difference between cold pressed and hot pressed (as long as hot doesn't exceed limits), or at least that is how I view it. Cold pressed hammers have a particular character in large part because they are limited by their process to a certain degree of tension and compression. That same degree of tension and compression could be created by a process using heat. Adding a certain amount of heat and extra pressure can produce a hammer with the additional compression it needs for certain applications, concert pianos being a prime example.

That, in any case, is how I have derived my own philosophical standpoint. Hot pressed hammers seem to me, in practice, to have just as much tension as cold pressed ones, even more, except that it is somewhat immobilized by the compression it is holding in. It can be adjusted fairly readily if the hammer has not gone over certain limits. But even extremely dense, over-compressed hammers can be worked so that they will function well, with enough work to undo what was over done.

In the case of gross over-lacquering, tension is definitely reduced, as the mass of felt becomes solidified by the addition of those solids. The opposing forces are more or less neutralized - the same could happen with over-felting the wool, like those felt "rocks" Jack Brand likes to throw around at some of his classes. So that is another discussion.

In any case, I think this thread has been a valuable one. It is always a good idea to challenge our assumptions, articulate our reasoning, and try to come up with a good working model on which to build effective procedures.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-24-2013 19:53
From: David Love
Subject: lacquer voicing

"Shouldn't be necessary", or "should be avoided" is probably an overstatement of my position. Minimized is a better way to put it. There will always be some work to do even if it's just balancing and smoothing within a given instrument. However, I think we can get much closer out of the box than we do currently if we choose correctly, or as I am suggesting, tailor the hammer attributes to the specific instrument, its impedance characteristics, and, of course, the tonal goal or model that you are trying to achieve. I do think that voicing procedures (needling, lacquer, and any other's you wish to mention) are destructive to the structural integrity of the hammer. Some more, some less but you cannot employ any procedure with total impunity.

In one sense we probably agree with respect to concert instruments. Their requirements owning to both the high impedance characteristics plus the somewhat unusual requirements of a 30-rows-out baseline ratchets things up a bit, sometimes a lot. Michael Spreeman's pianos, from what I gather, a 220cm and a 270cm (if I got that right) are both, relatively speaking, higher tension scales (as you would expect with those sizes) with soundboards designed to function in sync with those scales. Even so, The Voicing the Renner Blue Point demo that I saw in Seattle left the piano somewhat overly bright as reported by the pianist who road tested it after the class was done. There was more work to be done there and more work had been done than 7-8 strokes in the shoulder, at least from my observation. In fairness, I can't say that that was a definitive demonstration for that hammer. But I would guess before the Blue Point Michael used something with somewhat similar attributes. BTW and FWIW, I don't consider 7-8 strokes in the shoulder to be excessive, 50 is though. But put that same hammer on a very low tension, lightweight soundboard, a 1920 Steinway M, original board with much lower impedance characteristics than the Ravenscroft 270, and you will certainly find that there is much more work to do. Enough so that maybe a hammer designed somewhat differently to begin with would have been a better fit.

With respect to heat, we need to separate heat used in the fulling process of felt manufacturing from heat used in the making of hammer heads. They serve two distinctly different purposes. Any heat used in the hammer making process will impact tension. Excessive heat can destroy it completely. Now if you believe that tension is unimportant then that is another discussion and a worthwhile one for additional research. Hysteresis may well be the issue with respect to tension: how the spring-like quality of the hammer reacts during impact as opposed to following impact, the hammer's ability to recover its shape completely and at what rate after our elastic collision, implications for stability, and tonal implications as well. There are some articles that I've read that start to touch on this subject and it's very interesting, though I can't say I know the significance of it all at this point.

It's further complicated because "tensioned" doesn't precisely describe the nature of the hammer. The hammer is tensioned on the outside layers but compressed on the inside (near the core molding). There exists in objects like this what is called a neutral axis--a place some distance below the surface where the hammer is neither under tension nor compression but neutral, where it transitions from tension to compression, as it were. That's probably a dynamic axis, meaning it changes or moves, maybe as we file the hammer and/or as we needle, maybe as it's played and stressed under a series of collisions. All very interesting in explaining, perhaps, why hammers that you needle seem to initially get less "bright" but grow increasingly more bright when just left alone over the first day or two. The release of tension on the outside may move the neutral axis outward and effectively add tension back or increase the density of the outer layers. There are many other possible implications as well but it's beyond this writing certainly, and probably left to the research scientists, of which, I am not one.

But it does appear to me, from my own experience (and I have to rely on a symptomatic diagnoses lacking any good genetic markers or lab pathology reports) that hammers with a lot of tension have a somewhat different sound than hammers with no tension (or limited amounts of tension really--though there are some that seem to have none). They react differently to voicing protocols and have different levels of stability. Perhaps it's my imagination, but I don't think so. So far, I can't think of a reason why you wouldn't want to maximize tension in the hammer, especially as it impacts the hammer's ability to function in a spring-like manner. The cold pressing process seems to be the best way to do that. Quality felt is a necessary precursor and equally important in that it allows for adequate stretching (the manner in which tension is created). Other dimensional factors may play into this as well.

The idea that cold pressing means that the hammer will lack power is to ignore the other hammer attributes that I mentioned now several times in previous posts that can impact the upper end of power. When I speak of it that way I am really referring to the amount of energy absorbed by the hammer that will not get to the string/soundboard assembly. The F = MA equation does not differentiate between a cold-pressed hammer and a hot-pressed hammer. The question of power delivered becomes, then, not one of the amount of force, but how much energy does the hammer itself absorb making it unavailable to the soundboard system. That is, after all, what we do when we "voice a piano down". By making the hammer more compliant it absorbs more energy and dissipates it in some other form than acoustic energy. So the question becomes can the amount of energy that is absorbed and dissipated by the hammer itself be minimized when necessary even with the cold pressing process thus achieving the power that we need without compromising, or with a minimal compromise, of tension.

I think it can. But the entire spectrum of hammer attributes must be considered together. At least that is my current thinking.

Just a quick comment on the design/redesign thing. Whether you like it or not you are involved with piano design. The things that you have to do to pianos are a function of their design (and execution). How design contributes to performance is important even if you aren't designing pianos from the ground up. The more we know about the effects of design the better off we are.

But if by your comment you are suggesting that I am somehow coming to these conclusions based on my own interest in "redesigning" pianos, you are mistaken. While I do have experience in the "redesign arena", enough, to have informed and first hand experiences about what can happen, I am not driven by redesign in this hammer issue. My current projects, in fact, employ only very modest (if any) redesign features. My targets in this discussion are conventional pianos generally but may also include so-called redesigned pianos. Designs that really do push the tonal envelope may very well require something in terms of a specific combination of hammer attributes that is different from more conventional designs or approaches. But you can't lump them all together. The design elements between any two pianos, even conventional ones, will have inevitable overlaps and points where they diverge. Those similarities and differences cannot but summed up by the simple term "redesign".

Well this went on far longer than I intended.

Time to check in on Tiger Woods. Talk about redesign!



David Love
www.davidlovepianos.com

Well you've asked a lot of questions that I can't really answer, (molecular level stuff). But the evidence is not that far from our own observations. I've had discussions at length with both Jack Brand and Ray Negron about felt and hammer making and what creates and destroys tension and the felt making process. But some things are evident. I think it is true that any heat in the hammer making process will impact tension. This is not the same in the felt making process because heat (and there's quite a bit of it along with water and steam) is used there to shrink the felt to get a certain density, to compress it down from some relatively thick structure with little density to a much thinner one. When you through your wool sweater into the drier it shrinks. But since it is not under tension there can be no impact on the tension. With the felt not under tension there is no tension to be affected. When you are making the hammer head, on the other hand, the felt is put under tension and then heat is applied. The combination of heat while the felt is under tension can clearly alter the fibers in some way (the specific micro level mechanics are unknown to me at this point) such that a change in tension is evident. For example, in the pre pressing process, when the felt is basically pushed down into a u-shaped caul before the wood molding is inserted and glued into place (I'm assuming you are aware of the hammer making process) the caul that shoves it down is, in cold pressing, not heated. When that caul is withdrawn the felt under tension will spring back pretty much to its original shape, not instantly but at a fairly good rate. It is the tension in the felt that causes it to spring back. The outer layers (the convex side) is stretched and when the caul is removed the tension on that side pulls it back together and the felt sheet straightens out. The compressed layers on the opposite side also want to expand and assist in this. In some methods of hammer head making, the inner caul (as it's called) is heated. That may be done for various reasons, often that’s because the sheet of felt is very dense or thick and pushing it down into the u-shaped caul is difficult, or it is difficult to get the felt to stay there long enough to insure that you can insert the wood molding strip. The longer you leave the inner caul in place the more you put a permanent crease (as it were) in the sheet of felt such that at a certain point, when withdrawn, the felt will no longer spring back, or not to the same degree. Thus, when the sides of the sheet are pulled to the molding and glued down they require less, sometimes very little stretching to get them into place. In that case, the tension over the convex side of the hammer will have been reduced. Further, the compressed is altered as well, compressed by the heat, as it were, such that s no longer pushing back. Perhaps the compression of the inner side of the felt is more instrumental in the felt not wanting to spring back, but that may change the neutral axis some, I can't comment specifically about this balance, it's beyond my knowledge. However, what we see is that the sheet will not return to its original form. Once in place, then the outer cauls that press the outside part of the hammer can also be heated and often are, except in pure cold pressing. Sometimes that is for the purpose of adding density by, in effect, shrinking the felt. But now that part of the hammer is under tension. The amount of tension is more or less depending on what happened with the prepressing, the amount of stretching required to get the sides of the hammer to the molding and probably some other factors, but this should suffice. When heat is applied to the tensioned felt it changes. The fibers go through some physical change which I am hard pressed (pun intended) to explain on the micro level. When that hammer is cut away from the molding, if it is still under tension it will want to revert back to its original prepressed, preheated state. The degree to which it does not is an indication of the change in overall tension, certainly it represents a change in the compression/tension balance in some way but I am not sure how they are not interrelated. The amount of tension lost will be related to whether both the inner caul and the outer caul were heated, to what degree and how long they were left in place. But I think it's pretty clear that the tension is impacted, we can see it. Stretch your wool sweater over a form of some type and apply heat while it is stretched and I can assure you it will not fit you quite the same way when you are done. Cut the hammer off the molding (or split it down the middle from the strike point) and it will not spring back or open up as much on the hammer with less tension. Most hammers will maintain some degree of tension but the amount can vary. Add to that the needling process which inevitably takes place on hammers outer structure, where what tension there is is stored, and it's easy to see how the tank can run dry fairly quickly. How much heat "causes harm" becomes a matter of degree. All heat that is applied to the hammer while it is under tension (and compression) will alter that amount of tension or at least the balance between those two it seems to me. At what point does it become a real liability? That's a different question. Here we can only report anecdotally what we hear, how stable the hammer seems to be, how it reacts to the voicing process (whether sticking a needle in one area seems to affect the hammer in another area, probably a good sign of tension). I have noticed, for example, that hammers with less tension seem to require needling closer to the strike point in order to effect change in the tone. That is most obvious in a heavily lacquered hammer, devoid of tension, in which needling very near the crown or directly into the crown is necessary. Hammers that react over the strike point when needled farther away from it indicate, to me that tension in the outer fibers is being released and the effects can be far reaching. You have to be more careful when voicing near the crown in a highly tensioned hammer, generally speaking. I agree with you about lacquered hammers that they are devoid of tension at a certain point. With respect to "over-felting" and creating a felt which is too dense when in sheet form, there is probably a practical limit to what you can bend around a piece of wood. If you have a very dense piece of felt you simply can't bend it, especially if it's thick. You have to do that with some hydraulic press and use a fair amount of heat to give it a good crease. If the felt isn't of good quality you'll probably tear it or shatter the molding trying to press it down in there. It's often these big heavy dense hammers that seem to have the least amount of tension, at least as measured by cutting the felt off the molding. Interestingly, or so I am told. The sheets of felt used for the vintage Steinway hammers were lower density (compared to many of today's hammers) and the felt was thinner. This lower density and thinner felt allowed for more stretching of the material. The tension and density gained through more vigorous stretching was something that seems to have worked quite well. People like Norm Neblett, for example, often talked about those old hammers as being the gold standard. Whether they were or not, it's hard to tell now, but they were certainly part of the tonal triangle that helped Steinway to become who they are, or were. It seemed to work. Anyway, hot pressed hammers do not have as much tension as cold pressed ones I'm convinced, a least according to all the felt and hammer making people that I've spoken with. Where the line of not enough tension is crossed is certainly a discussion that one can, and should, have. But for me, I prefer a hammer that has the maximum amount of tension. And not to beat a dead horse, but tension is only one attribute of hammers that needs to be considered. Density, profile, weight, felt quality, also need to be considered as well as how those attributes interact. Forgive the typos (no time to proof carefully), hopefully I didn't make too many. Good thread, agreed. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Wednesday, March 27, 2013 2:01 PM To: David Love Subject: Voicing: RE:lacquer voicing David, Thanks for a great, detailed post. I think most of it is spot on. The one, rather basic, point that I would take issue is "Any heat used in the hammer making process will impact tension." I guess we might need to define just what we mean by tension, as it functions within the structure of the hammer, and that becomes partly a matter of speculation (as in what you described as the area where tension and compression cross - a good conceptualization, and your thoughts about the shifting of compression and tension as a result of the needling process were spot on IMO). I start from the premise that there is a certain amount of heat that will not, for our purposes, cause harm to the fibers themselves. For those who are purists, and say that any heat harms wool fibers, I would simply point out that felt hammers would be impossible without steam, which is hotter than boiling point, and that that amount of heat has to be acceptable, period. You can felt without that much heat, but not to the density needed for piano hammers. Now suppose we start with a given felt strip, and press two sets of hammers using it, with every variable precisely the same except that in one case we will apply some moderate heat, within the limits used in fulling processes, and the other will be cold. What will be the difference in the hammer sets? I haven't done the experiment, but I believe from all sorts of analogous experiences and from what I have read, that it is likely the differences would be fairly minimal. Do you have any evidence that this is not the case? What effect does heat have in the pressing process? On the molecular level, it makes the proteins in the fibers more compliant, less springy, while the heat is present, so that they are less resistant to being stretched or compressed. The individual fibers, millions of them, are acting together, but on an individual basis it has to do with the crimp, the curl of the fiber, and how much it is being stretched straight or bent. Together, these millions of interlocked fibers are being stretched and compressed, some one and some the other, some being pulled more straight while others, by accident of how they are aligned are being bent. If we simply heat and compress, then release, a certain amount of compression will be retained, but the material will not have been "felted" into that extra compression, and the compression will reverse with time or a certain amount of "working" or application of steam. If you add heat to the whole mass, it is possible to stretch and compress the whole mass quite a bit more with the same amount of pressure, so you can fit more felt into the same space in the cauls and press the whole into what will be a tighter and more compressed mass. Fixing the ends by glue and staples to the molding that maintains the tension that holds the compression in a more or less static state. Heat allows pressing to a more compressed state than would be possible with cold pressing, because the felt cannot be stretched or compressed as much without that heat. The tension can be brought to a higher level with heat, resulting in more compression - though where the "boundary between the two" lies may be different from in a less densely pressed hammer, to the extent that it is hard to discern the tension because the compression is more noticeable (but that compression couldn't be there without the presence of the tension). So it is really the choice of how much additional pressure (whether by cramming more felt in, starting with denser felt, or other variables) that determines the major difference between cold pressed and hot pressed (as long as hot doesn't exceed limits), or at least that is how I view it. Cold pressed hammers have a particular character in large part because they are limited by their process to a certain degree of tension and compression. That same degree of tension and compression could be created by a process using heat. Adding a certain amount of heat and extra pressure can produce a hammer with the additional compression it needs for certain applications, concert pianos being a prime example. That, in any case, is how I have derived my own philosophical standpoint. Hot pressed hammers seem to me, in practice, to have just as much tension as cold pressed ones, even more, except that it is somewhat immobilized by the compression it is holding in. It can be adjusted fairly readily if the hammer has not gone over certain limits. But even extremely dense, over-compressed hammers can be worked so that they will function well, with enough work to undo what was over done. In the case of gross over-lacquering, tension is definitely reduced, as the mass of felt becomes solidified by the addition of those solids. The opposing forces are more or less neutralized - the same could happen with over-felting the wool, like those felt "rocks" Jack Brand likes to throw around at some of his classes. So that is another discussion. In any case, I think this thread has been a valuable one. It is always a good idea to challenge our assumptions, articulate our reasoning, and try to come up with a good working model on which to build effective procedures. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

I guess the bottom line is that there are some aspects we just don't know about. My assumption is that heat and pressure do not actually act to increase the felting of the fibers - the fibers are not entangled more so that they hold themselves into a more dense matrix - but OTOH there is a certain degree of compression with heat that lasts, as in that pre-creasing of the felt before the actual pressing and gluing of the hammers. I have seen video and pictures of that, and there is no question that the dent stays more with heat.

Similarly one can get a "semi-permanent" dimensional change with key bushing cloth, either with heated cauls (bushings already installed) or by ironing firmly, but it is quite limited in the amount of change, and reversible: simply steam and the felt comes back to original dimension or expands farther. The more permanent felting requires moisture and agitation, along with heat and pressure.

As that applies to hammers, to what happens to the felt when the hammers are pressed, I think there is probably a certain amount of "setting" of the felt caused by heat, but I also think that setting is pretty easily reversible by a moderate amount of shoulder needling. One way to get at the tension/compression thing in hammers is to do what Abel does in some hammer classes: saw a kerf down the middle of the molding of a hammer, to the point, and observe how much the hammer opens, and how much "spring" there is when you close the gap again. This varies quite a bit from hammer to hammer (ie, different makes and pressings). I've done it on a few, and the results are revealing. More interesting in the context of this conversation is the effect of shoulder needling.

I thought I would take some pictures of that process: saw the kerf and measure the opening formed by the tension of the felt pulling the hammer open. Then put the hammer in a vise (closing the gap and holding it firmly in place) and deep needle the shoulder. And then measure the opening again. I took an Abel hammer, from Brooks, never used, and did what I described, and the accompanying photos show the results: initial opening of about 7 mm (at tail). After needling, 6 - 7 strokes, 10 - 11 mm long three needle, the opening was 12 mm. A second needling (same) and the opening was 14 mm. And the hammer felt "springier" (ie, squeezing the tail together there was more resistance). I did the same for an Abel Natural, and got the same results. I did that first, and failed to take the first photo, so you'll have to trust me.

I'd be interested in doing some additional fooling around of this sort, especially adding lacquer to the mix, and maybe I will when I get the time. Unfortunately most of my hammer "archives" are well used, and this sort of thing should really be done with fresh hammers, where you know there was no initial needling or lacquering, or at least you know precisely what had been done. Steinway sets don't have extra hammers to sacrifice to this kind of experiment, unfortunately.

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 03-27-2013 18:09
From: David Love
Subject: lacquer voicing

Well you've asked a lot of questions that I can't really answer, (molecular level stuff). But the evidence is not that far from our own observations. I've had discussions at length with both Jack Brand and Ray Negron about felt and hammer making and what creates and destroys tension and the felt making process. But some things are evident.

I think it is true that any heat in the hammer making process will impact tension. This is not the same in the felt making process because heat (and there's quite a bit of it along with water and steam) is used there to shrink the felt to get a certain density, to compress it down from some relatively thick structure with little density to a much thinner one. When you through your wool sweater into the drier it shrinks. But since it is not under tension there can be no impact on the tension. With the felt not under tension there is no tension to be affected.

When you are making the hammer head, on the other hand, the felt is put under tension and then heat is applied. The combination of heat while the felt is under tension can clearly alter the fibers in some way (the specific micro level mechanics are unknown to me at this point) such that a change in tension is evident. For example, in the pre pressing process, when the felt is basically pushed down into a u-shaped caul before the wood molding is inserted and glued into place (I'm assuming you are aware of the hammer making process) the caul that shoves it down is, in cold pressing, not heated. When that caul is withdrawn the felt under tension will spring back pretty much to its original shape, not instantly but at a fairly good rate. It is the tension in the felt that causes it to spring back. The outer layers (the convex side) is stretched and when the caul is removed the tension on that side pulls it back together and the felt sheet straightens out. The compressed layers on the opposite side also want to expand and assist in this.

In some methods of hammer head making, the inner caul (as it's called) is heated. That may be done for various reasons, often that’s because the sheet of felt is very dense or thick and pushing it down into the u-shaped caul is difficult, or it is difficult to get the felt to stay there long enough to insure that you can insert the wood molding strip. The longer you leave the inner caul in place the more you put a permanent crease (as it were) in the sheet of felt such that at a certain point, when withdrawn, the felt will no longer spring back, or not to the same degree. Thus, when the sides of the sheet are pulled to the molding and glued down they require less, sometimes very little stretching to get them into place. In that case, the tension over the convex side of the hammer will have been reduced. Further, the compressed is altered as well, compressed by the heat, as it were, such that s no longer pushing back. Perhaps the compression of the inner side of the felt is more instrumental in the felt not wanting to spring back, but that may change the neutral axis some, I can't comment specifically about this balance, it's beyond my knowledge. However, what we see is that the sheet will not return to its original form.

Once in place, then the outer cauls that press the outside part of the hammer can also be heated and often are, except in pure cold pressing. Sometimes that is for the purpose of adding density by, in effect, shrinking the felt. But now that part of the hammer is under tension. The amount of tension is more or less depending on what happened with the prepressing, the amount of stretching required to get the sides of the hammer to the molding and probably some other factors, but this should suffice. When heat is applied to the tensioned felt it changes. The fibers go through some physical change which I am hard pressed (pun intended) to explain on the micro level. When that hammer is cut away from the molding, if it is still under tension it will want to revert back to its original prepressed, preheated state. The degree to which it does not is an indication of the change in overall tension, certainly it represents a change in the compression/tension balance in some way but I am not sure how they are not interrelated.

The amount of tension lost will be related to whether both the inner caul and the outer caul were heated, to what degree and how long they were left in place. But I think it's pretty clear that the tension is impacted, we can see it. Stretch your wool sweater over a form of some type and apply heat while it is stretched and I can assure you it will not fit you quite the same way when you are done. Cut the hammer off the molding (or split it down the middle from the strike point) and it will not spring back or open up as much on the hammer with less tension. Most hammers will maintain some degree of tension but the amount can vary. Add to that the needling process which inevitably takes place on hammers outer structure, where what tension there is is stored, and it's easy to see how the tank can run dry fairly quickly.

How much heat "causes harm" becomes a matter of degree. All heat that is applied to the hammer while it is under tension (and compression) will alter that amount of tension or at least the balance between those two it seems to me. At what point does it become a real liability? That's a different question. Here we can only report anecdotally what we hear, how stable the hammer seems to be, how it reacts to the voicing process (whether sticking a needle in one area seems to affect the hammer in another area, probably a good sign of tension). I have noticed, for example, that hammers with less tension seem to require needling closer to the strike point in order to effect change in the tone. That is most obvious in a heavily lacquered hammer, devoid of tension, in which needling very near the crown or directly into the crown is necessary. Hammers that react over the strike point when needled farther away from it indicate, to me that tension in the outer fibers is being released and the effects can be far reaching. You have to be more careful when voicing near the crown in a highly tensioned hammer, generally speaking.

I agree with you about lacquered hammers that they are devoid of tension at a certain point. With respect to "over-felting" and creating a felt which is too dense when in sheet form, there is probably a practical limit to what you can bend around a piece of wood. If you have a very dense piece of felt you simply can't bend it, especially if it's thick. You have to do that with some hydraulic press and use a fair amount of heat to give it a good crease. If the felt isn't of good quality you'll probably tear it or shatter the molding trying to press it down in there. It's often these big heavy dense hammers that seem to have the least amount of tension, at least as measured by cutting the felt off the molding.

Interestingly, or so I am told. The sheets of felt used for the vintage Steinway hammers were lower density (compared to many of today's hammers) and the felt was thinner. This lower density and thinner felt allowed for more stretching of the material. The tension and density gained through more vigorous stretching was something that seems to have worked quite well. People like Norm Neblett, for example, often talked about those old hammers as being the gold standard. Whether they were or not, it's hard to tell now, but they were certainly part of the tonal triangle that helped Steinway to become who they are, or were. It seemed to work.

Anyway, hot pressed hammers do not have as much tension as cold pressed ones I'm convinced, a least according to all the felt and hammer making people that I've spoken with. Where the line of not enough tension is crossed is certainly a discussion that one can, and should, have. But for me, I prefer a hammer that has the maximum amount of tension. And not to beat a dead horse, but tension is only one attribute of hammers that needs to be considered. Density, profile, weight, felt quality, also need to be considered as well as how those attributes interact.

Forgive the typos (no time to proof carefully), hopefully I didn't make too many. Good thread, agreed.

David Love
www.davidlovepianos.com

I think we are safe in making some inferences The felting process is that in which the fibers are mixed and interlinked as such. The fulling process is where the felt is shrunk to the desired density. How much additional interlocking happens in the fulling process I don't know, but most of seems to be done in the felting process. I think that is correct but if not then someone will hopefully clarify. I'm not sure it matters for our discussion though. Yes the "dent" stays with more heat, I'm not sure what you are saying. It's the stretching of the felt that causes tension on the outside of the hammer. The core of the hammer is under compression. It's the pulling (and pushing) of the felt that causes it to open up again when you slice it open. When you needle the shoulders are you increasing the tension? Or are you making the hammer less dense on the outer area of the hammer and thus allowing the compressed area in the core of the hammer to push things apart more? It's probably both but in the tensioned hammer there is a pulling toward the crown from either side that assists. As you remove that tension it pulls less. That doesn't necessarily mean that the pushing from the compressed part of the hammer changes. In an uncreased hammer with no heat to remove tension on the outside, the opening of the hammer will be greatest as you have both maximum pushing and pulling. I think we can infer that. Getting a semi-dimensional change when you iron a bushing is not quite the same. The bushing is not under any type of stress and the tension is not altered, only the density. You are heating and shrinking the felt and also chasing unwanted moisture. As the felt absorbs moisture again it will expand. Ironing bushings for that reason can be somewhat impermanent. Sizing the mortise properly is more important than trying to make up for that by ironing the felt. BTW the moisture content of the felt when it goes into the press is important. Too much moisture and the hammer will shrink in the press (especially if heat is applied) and it can lose tension. Some hammer makers (the better ones) will keep the sheets in a RH controlled space prior to pressing for just that reason. Felt with high EMC tends to come out with less tension than felt with lower EMC. I'm still convinced that cold pressing preserves more tension in the hammer and that needling releases tension. Voicing hammers that have little or no tension versus voicing hammers that have lots of tension will not only involve slightly different target areas, IMO, but will yield different tonal results with different levels of permanence owning to the tensioned hammer's more elastic quality versus basically packing down felt as will happen in the density style hammer. When you open up a hammer with no tension you are basically altering its density, strategically, of course. When you open up a hammer that has lots of tension, you are allowing the spring to expand some. In that way it's not surprising the tensioned hammers are a bit more sensitive, easier to overdo and harder to correct than density driven hammers. It's hard to put tension back, it's relatively easy to "redensify" a hammer. In fact, once the tension in the tensioned hammer is dissipated by needling, you have effectively converted it into a hammer that will have to be treated as a density driven hammer. The dynamic qualities of the two are different, I believe, and I think you can hear that. The lacquered hammer versus the tensioned hammer illustrates that difference the best. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Monday, April 01, 2013 10:19 AM To: David Love Subject: Voicing: RE:lacquer voicing I guess the bottom line is that there are some aspects we just don't know about. My assumption is that heat and pressure do not actually act to increase the felting of the fibers - the fibers are not entangled more so that they hold themselves into a more dense matrix - but OTOH there is a certain degree of compression with heat that lasts, as in that pre-creasing of the felt before the actual pressing and gluing of the hammers. I have seen video and pictures of that, and there is no question that the dent stays more with heat. Similarly one can get a "semi-permanent" dimensional change with key bushing cloth, either with heated cauls (bushings already installed) or by ironing firmly, but it is quite limited in the amount of change, and reversible: simply steam and the felt comes back to original dimension or expands farther. The more permanent felting requires moisture and agitation, along with heat and pressure. As that applies to hammers, to what happens to the felt when the hammers are pressed, I think there is probably a certain amount of "setting" of the felt caused by heat, but I also think that setting is pretty easily reversible by a moderate amount of shoulder needling. One way to get at the tension/compression thing in hammers is to do what Abel does in some hammer classes: saw a kerf down the middle of the molding of a hammer, to the point, and observe how much the hammer opens, and how much "spring" there is when you close the gap again. This varies quite a bit from hammer to hammer (ie, different makes and pressings). I've done it on a few, and the results are revealing. More interesting in the context of this conversation is the effect of shoulder needling. I thought I would take some pictures of that process: saw the kerf and measure the opening formed by the tension of the felt pulling the hammer open. Then put the hammer in a vise (closing the gap and holding it firmly in place) and deep needle the shoulder. And then measure the opening again. I took an Abel hammer, from Brooks, never used, and did what I described, and the accompanying photos show the results: initial opening of about 7 mm (at tail). After needling, 6 - 7 strokes, 10 - 11 mm long three needle, the opening was 12 mm. A second needling (same) and the opening was 14 mm. And the hammer felt "springier" (ie, squeezing the tail together there was more resistance). I did the same for an Abel Natural, and got the same results. I did that first, and failed to take the first photo, so you'll have to trust me. I'd be interested in doing some additional fooling around of this sort, especially adding lacquer to the mix, and maybe I will when I get the time. Unfortunately most of my hammer "archives" are well used, and this sort of thing should really be done with fresh hammers, where you know there was no initial needling or lacquering, or at least you know precisely what had been done. Steinway sets don't have extra hammers to sacrifice to this kind of experiment, unfortunately. ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

Just to get our terminology right, to the best of my knowledge fulling is done to woven cloth: it is the process of turning a woven wool cloth into something like bushing cloth or the cloth for billiard tables. It is more or less "felting" woven cloth, as the woven threads become matted together and less distinct, and the cloth becomes more dense and resistant to wind and rain (as clothing).

Felting per se is a process without any weaving involved. The fibers are cleaned, laid out in some fashion, and then worked on with water, heat, agitation, and pressure, which makes all the individual fibers tangle amongst themselves, becoming denser and denser. This does have the effect of "shrinking," as the mass of wool fiber becomes much more compact in every dimension. Here is a decent article on the two terms.

Now as to the presence of tension in a hammer, I disagree that tension is "absent" in a hard pressed hammer, one that has been pressed with heat as opposed to cold pressed. But perhaps that is partly a matter of how we define tension. For our purposes in dealing with hammers, there is a dynamic tension that involves the "springy" movement of the mass of fibers within the hammer, and it is this dynamic tension that we are adjusting when we needle.

A very hard pressed hammer will have so much tension that there is very little space between fibers, hence very little possibility of movement. But the tension in definitely there, at least as I perceive the use of that word. Tension in hammers is the pulling/pushing (the cauls push, but it is easier to think of as a pull) of the outer layers of the felt around the molding, compressing the inner layers. On a more microscopic scale, individual fibers (some of them, or some parts of them) are stretched, meaning that their crimp (or natural bends when they are free to assume their natural form) is pulled straighter. But there are other fibers in different alignments that are being forced into new bends that they didn't have naturally, or those bends are more extreme in the position they are forced into. These fibers are resisting the tension of the fibers that are being straightened.

There are millions of fibers in the matrix, but this is the basic fact: some are being pulled straight, others are being forced into less straight alignments, and the interlocking via the scales on the individual fibers is allowing this to happen as a matrix. Those "interlocks" BTW are not particularly strong, individually, at least as I interpret the many electron microscope images I have seen. They have strength because of the number of them, the additive nature of so many fibers tangled together.

In any case, when a hammer is heat pressed (and for argument's sake, let us assume it is not so hot as to harm the fibers), the heat allows for a more dense pressing, and a more tense pulling around the molding (the fibers are more compliant when hot, easier to stretch and bend). As a result, there can be more tension and more compression. But when you get to a certain level of density, the tension and compression are no longer very active, the whole mass becomes static and more "rock-like." To activate the tension, it is necessary to loosen the fibers, so that they are able to move.

Even extremely hard pressed hammers like Tokiwas of the 80s have plenty of tension and compression in them. With enough judicious working, whether entirely with needles or with the assistance of other methods, they can function as quite reasonable piano hammers, producing a decent tonal gradient. I suppose that inserting the needles does reduce the tension (and compression), but that is not a problem because both are excessive. (I believe you are saying that there is no tension in such a hammer, and this is a basic disagreement we have). What we want is a gradient of tension and compression, and we get there by loosening up the fiber matrix.

I much prefer to work with hammers that are less densely pressed, with enough room between fibers to allow the felt to move more easily. But I need a fairly high degree of density in the crown area for nearly all my customers (largely University, concert venue, professional pianists - at least those customers I do serious hammer work for), and I simply have never found a cold pressed hammer that had adequate density there. So I am happy to compromise and choose what I consider to be a range of moderately hard-pressed hammers, in preference to having to lacquer - though I lacquer as well, and the results are quite satisfactory. The tonal results are somewhat different, and for me that is a good thing, as I like variety (both as pianist and technician). But I am surprised at how small the difference often is. I often don't remember which style hammer I put on the piano I am tuning, and it is not obvious at all, either while tuning or when I play the instrument, especially in an "in between" state (after a couple months hard playing without voicing touch up).

-------------------------------------------
Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
-------------------------------------------






Original Message:
Sent: 04-01-2013 14:39
From: David Love
Subject: lacquer voicing

I think we are safe in making some inferences

The felting process is that in which the fibers are mixed and interlinked as such. The fulling process is where the felt is shrunk to the desired density. How much additional interlocking happens in the fulling process I don't know, but most of seems to be done in the felting process. I think that is correct but if not then someone will hopefully clarify. I'm not sure it matters for our discussion though. Yes the "dent" stays with more heat, I'm not sure what you are saying. It's the stretching of the felt that causes tension on the outside of the hammer. The core of the hammer is under compression. It's the pulling (and pushing) of the felt that causes it to open up again when you slice it open. When you needle the shoulders are you increasing the tension? Or are you making the hammer less dense on the outer area of the hammer and thus allowing the compressed area in the core of the hammer to push things apart more? It's probably both but in the tensioned hammer there is a pulling toward the crown from either side that assists. As you remove that tension it pulls less. That doesn't necessarily mean that the pushing from the compressed part of the hammer changes. In an uncreased hammer with no heat to remove tension on the outside, the opening of the hammer will be greatest as you have both maximum pushing and pulling. I think we can infer that.

Getting a semi-dimensional change when you iron a bushing is not quite the same. The bushing is not under any type of stress and the tension is not altered, only the density. You are heating and shrinking the felt and also chasing unwanted moisture. As the felt absorbs moisture again it will expand. Ironing bushings for that reason can be somewhat impermanent. Sizing the mortise properly is more important than trying to make up for that by ironing the felt.

BTW the moisture content of the felt when it goes into the press is important. Too much moisture and the hammer will shrink in the press (especially if heat is applied) and it can lose tension. Some hammer makers (the better ones) will keep the sheets in a RH controlled space prior to pressing for just that reason. Felt with high EMC tends to come out with less tension than felt with lower EMC.

I'm still convinced that cold pressing preserves more tension in the hammer and that needling releases tension.

Voicing hammers that have little or no tension versus voicing hammers that have lots of tension will not only involve slightly different target areas, IMO, but will yield different tonal results with different levels of permanence owning to the tensioned hammer's more elastic quality versus basically packing down felt as will happen in the density style hammer.

When you open up a hammer with no tension you are basically altering its density, strategically, of course. When you open up a hammer that has lots of tension, you are allowing the spring to expand some. In that way it's not surprising the tensioned hammers are a bit more sensitive, easier to overdo and harder to correct than density driven hammers. It's hard to put tension back, it's relatively easy to "redensify" a hammer. In fact, once the tension in the tensioned hammer is dissipated by needling, you have effectively converted it into a hammer that will have to be treated as a density driven hammer. The dynamic qualities of the two are different, I believe, and I think you can hear that. The lacquered hammer versus the tensioned hammer illustrates that difference the best.

David Love
www.davidlovepianos.com

Hi David,

Just getting in on this discussion..... My wife Eleanor is a feltmaker and we've had a lot of experience visiting felt making factories and working with wool.  In fact I'm making wool hats today...   anyway..... The fulling process is a felting process just with more pressure.   To make really hard felt the wool batts are first  pressed between large hot plates and vibrated.  The heat and water opens the scales on the fiber and the vibration interlocks the fibers.  The hot/wet opened scales act like ratchets.   Only so much density is achieved this initial "hardening" process like for damper felts, butt felts, and the like.  To get higher density such as back check or hammer felt, higher pressure is needed in the "fulling" process.   Hammer felt is fulled by pounding with powerful wood faced hammers in a fulling mill for many hours.  The sheet comes out of the mill and is dried and pressed to take out unevenness in the fulling.  So to some degree hammer felt sheets are hot pressed before they even make it to the hammer makers.  The higher the quality of the manufacturing the less hot pressing of the sheets is needed after fulling to make the hammer makers specs.   Density that is achieved by fulling has more fiber interlocking than density that is achieved by hot pressing.  hope this helps.

David Stanwood

From: David Love
Posted: Monday April 1, 2013  2:40 PM
Subject: RE: lacquer voicing
Message: I think we are safe in making some inferences

>Snip> The felting process is that in which the fibers are mixed and interlinked
>as such.  The fulling process is where the felt is shrunk to the desired
>density.  How much additional interlocking happens in the fulling process I
>don't know, but most of seems to be done in the felting process.  I think
>that is correct but if not then someone will hopefully clarify. <snip>

Great analogy, David:
... when I step outside and stick my finger into the breeze, I don't think about my latitude, elevation, proximity to the ocean, mountain ranges, humidity, coriolis effect, ocean currents, or any other factors ..."

and:

"...  Good discussion. ..."

Yes, indeed. Thanks one and all.

Keith McGavern, RPT
Shawnee, Oklahoma, USA
tune-repair@allegiance.tv
-------------------------------------------

Fred: No point in disputing felting versus fulling. There are several basic steps to wash, process, mix and interlock the felt create these thin little sheets which are stacked up on top of each other and then take this 12 inch or whatever thick pile of wool sheets and reduce it to a thinner and more dense piece of felt. The use of oscillating rollers, steam and heat in that later part also serves to further interlock the fibers. The result of good hammer felt making is a uniformly dense sheet of felt that is well interlocked and where the fibers are not damaged. The Weickert process is considered to be superior in terms of controlled and uniform density (over Bacon, VFG, "Japanese" methods): a good blend of both long and short fibers, health of the fiber when the process is over (not too many harsh chemicals that strip the felt of its natural substances), and the degree of interlocking. That's why the best hammer makers want it and use it. That's probably sufficient for our purposes however we wish to call the processes. You need to be careful with straw man arguments here. You are misrepresenting what I have said before making an argument against it. I never said that tension was "absent" in a "hard pressed hammer". You can press a hammer very hard and it can have tension in it. The starting density of the sheet can impact how much stretching can be done but that is another issue. I said that the use of heat in the process of hammer making has an effect on tension, it lessens it, it does not increase it. The application of heat while the hammer is under tension alters the fibers structurally. But even with the use of heat there will likely be some tension, just less. Too much heat, however, and you can effectively destroy any or most tension. Since the voicing process itself (needling) reduces tension further, then starting with less leaves you with less to work with and it is more quickly dissipated. If the debate is whether you want or need tension at all in a hammer, that's fine. You can argue that. I don't agree, but it's point that can be debated. A hammer without tension will still hit the string and impart energy. Neither am I suggesting you can't get acceptable results with hammers with less tension, or no tension for that matter. With some skill you can make just about anything work, even work fairly well, we do it all the time. I'm talking about what is desirable. I can't see a reason to reduce or eliminate tension in a hammer on purpose before you even start under pretty much any circumstances. Heat is the main culprit in that. The interlocking fibers are, in fact, quite strong. Otherwise the felt will tear (or the molding will fracture if you are trying to shove it down into the caul without some prepressing). Poorer felt, in fact, can and does tear and the amount of stretching that can be done can be limited by that. Lack of space between the fibers does not insure that there is more tension (or less for that matter). You can have dense felt with no tension or not so dense felt with lots of tension. In terms of your experiment of cutting hammers apart, the less dense Bacon felt often opens the most in that experiment. Tension is not to do with the cauls, though they have a role in stretching the felt in the pressing process. The tension is in the felt and is only created through stretching. If the felt is not stretched there will be no tension. That's what tension is, it's the pulling of the felt in the opposite direction from which it has been or is being stretched. Once that stretching force is removed, there is no more tension. I don’t see how you can introduce stretching by needling. Needling releases (removes) tension. I suppose that if you could expand the felt from underneath the hammer surface so that it stretched the outer layers then you could introduce tension into the outer layers of the hammer. But when you "needle" hammers, you needle from the outside in (generally). So when you say loosen the fibers (I assume you mean the outer fibers) to increase the tension that doesn't make sense to me. By "loosening" the fibers you are necessarily releasing or removing tension in the outer layers (they are no longer as stretched since you've now separated the fibers some. Just as when you loosen your elastic belt you remove tension from it. Your stomach may expand and reintroduce some tension back into your belt with, perhaps, some room to move now, but then you are saying that the release of tension of the outer layers that is constricting the hammer allows the hammer to expand and therefore introduces more tension into the outer fibers than was there in the first place. Not sure I buy that. You may well "open up" the hammer, an apt description, but you are not, as I see it, increasing tension. I suppose you could argue that deep needling expands the layers underneath more than the piercing of the outer layers removes tension that is either there or forming (or both) on the outside of the hammer. I can't comment on that. I'll have to rely on the scientists there. What I hear and the manner in which I see the hammers respond doesn't seem to suggest that however. Rather, I think in that case you are simply making the hammer less dense, allowing it some room to compress thus introducing a degree of flexibility into an otherwise rigid body. Cleary that does work and is an important structural consideration when voicing hammers that have no tension but are simply too dense. We do this all the time with hammers that are too hard and have devised all kinds of enhanced interrogation techniques to accomplish this including: pliers, steam, water, dremel tools, needles, fabric softeners and vodka (such a waste). But creating a "density gradient" should not be mistaken for introducing tension that is somehow hidden in the hammer or confused with what happens in a tensioned hammer when you release tension by needling. A portion of the density in a hammer that is under tension is a function of the tension itself. As you needle and release the tension from the outer layers, the hammer becomes less dense. It's more complicated, of course, because in a tensioned hammer it seems that you can release tension in certain parts of the hammer to impact the density in other parts of the hammer. When you needle tensioned hammers low in the shoulders they can get brighter, or louder. There may be other reasons for that too which are beyond this discussion, already too long. But when the tension is gone, your only hope to replace the density lost by the loss of tension is to basically pack the hammer down--the ultimate fate of even the most tensioned hammer. That won't return the tension to the outer layers, it simply provides the next best substitute. That's why we should treat the tension in hammers as a limited commodity, something to preserve and be cautious with. Every needle stick lets air out of the balloon. In many ways hammers with no tension that are simply density driven are easier and less sensitive to voicing mistakes. Hammers filled with lacquer, for example, can take all kinds of abuse: make then harder, make them softer, needles in the crown, you can get away with a lot. Good, well matched to the belly (doesn't always happen), tensioned hammers sound better, I think, more lively, more resilient, more open, more bounce, but they require more of a surgeon's touch. You can make a mistake and let all the air out of the balloon at once if you are too aggressive and not careful. Who knows, maybe that's the reason they are not valued as much. I could be wrong, of course. Wouldn't be the first time (or the last). But I don't think so. David Love www.davidlovepianos.com
Original Message----- From: Fred Sturm [mailto:noreply@egroups.ptg.org] Sent: Monday, April 01, 2013 8:37 PM To: David Love Subject: Voicing: RE:lacquer voicing Just to get our terminology right, to the best of my knowledge fulling is done to woven cloth: it is the process of turning a woven wool cloth into something like bushing cloth or the cloth for billiard tables. It is more or less "felting" woven cloth, as the woven threads become matted together and less distinct, and the cloth becomes more dense and resistant to wind and rain (as clothing). Felting per se is a process without any weaving involved. The fibers are cleaned, laid out in some fashion, and then worked on with water, heat, agitation, and pressure, which makes all the individual fibers tangle amongst themselves, becoming denser and denser. This does have the effect of "shrinking," as the mass of wool fiber becomes much more compact in every dimension. Here is a decent article on the two terms. Now as to the presence of tension in a hammer, I disagree that tension is "absent" in a hard pressed hammer, one that has been pressed with heat as opposed to cold pressed. But perhaps that is partly a matter of how we define tension. For our purposes in dealing with hammers, there is a dynamic tension that involves the "springy" movement of the mass of fibers within the hammer, and it is this dynamic tension that we are adjusting when we needle. A very hard pressed hammer will have so much tension that there is very little space between fibers, hence very little possibility of movement. But the tension in definitely there, at least as I perceive the use of that word. Tension in hammers is the pulling/pushing (the cauls push, but it is easier to think of as a pull) of the outer layers of the felt around the molding, compressing the inner layers. On a more microscopic scale, individual fibers (some of them, or some parts of them) are stretched, meaning that their crimp (or natural bends when they are free to assume their natural form) is pulled straighter. But there are other fibers in different alignments that are being forced into new bends that they didn't have naturally, or those bends are more extreme in the position they are forced into. These fibers are resisting the tension of the fibers that are being straightened. There are millions of fibers in the matrix, but this is the basic fact: some are being pulled straight, others are being forced into less straight alignments, and the interlocking via the scales on the individual fibers is allowing this to happen as a matrix. Those "interlocks" BTW are not particularly strong, individually, at least as I interpret the many electron microscope images I have seen. They have strength because of the number of them, the additive nature of so many fibers tangled together. In any case, when a hammer is heat pressed (and for argument's sake, let us assume it is not so hot as to harm the fibers), the heat allows for a more dense pressing, and a more tense pulling around the molding (the fibers are more compliant when hot, easier to stretch and bend). As a result, there can be more tension and more compression. But when you get to a certain level of density, the tension and compression are no longer very active, the whole mass becomes static and more "rock-like." To activate the tension, it is necessary to loosen the fibers, so that they are able to move. Even extremely hard pressed hammers like Tokiwas of the 80s have plenty of tension and compression in them. With enough judicious working, whether entirely with needles or with the assistance of other methods, they can function as quite reasonable piano hammers, producing a decent tonal gradient. I suppose that inserting the needles does reduce the tension (and compression), but that is not a problem because both are excessive. (I believe you are saying that there is no tension in such a hammer, and this is a basic disagreement we have). What we want is a gradient of tension and compression, and we get there by loosening up the fiber matrix. I much prefer to work with hammers that are less densely pressed, with enough room between fibers to allow the felt to move more easily. But I need a fairly high degree of density in the crown area for nearly all my customers (largely University, concert venue, professional pianists - at least those customers I do serious hammer work for), and I simply have never found a cold pressed hammer that had adequate density there. So I am happy to compromise and choose what I consider to be a range of moderately hard-pressed hammers, in preference to having to lacquer - though I lacquer as well, and the results are quite satisfactory. The tonal results are somewhat different, and for me that is a good thing, as I like variety (both as pianist and technician). But I am surprised at how small the difference often is. I often don't remember which style hammer I put on the piano I am tuning, and it is not obvious at all, either while tuning or when I play the instrument, especially in an "in between" state (after a couple months hard playing without voicing touch up). ------------------------------------------- Fred Sturm University of New Mexico fssturm@unm.edu http://fredsturm.net "The true sign of intelligence is not knowledge, but imagination." - Einstein -------------------------------------------

With respect to the use of the term "fulling" in the process of making hammer felt, I defer to David Stanwood or others for current usage. My understanding of the term has to do with its longer historic use (back to Roman times, and the English term seems to derive directly from the Latin), which was directed at a range of processes by which woven wool cloth was altered so as to be, essentially, partially felted, and which included many distinct activities, one of which was pounding. That's a subject that has long interested me, and I have read quite a bit about it over the years (first got interested from Don Quixote, a scene where he hears the sound of a hammer mill - a water mill pounding wooden hammers on wool cloth to "full" it - and imagines other things).

I guess the term "fulling" has been transferred to mean pounding and a couple related processes in the making of non-woven felt, something that came later in history. These matters of word usage are not  particularly germane to the topic, but of interest as it does apply to other wools used in pianos, particularly such things as bushing cloth, which is a "fulled cloth" (as opposed to a felt). What does matter to our discussion is the final, unwoven hammer felt product (or range of products), a dense unwoven felt in which fibers are "interlocked."

In any case, I think the nub of where we have competing viewpoints lies in our use of the word "tension." I have been trying to explain my mental conception, perhaps not clearly enough. It might be helpful to distinguish between what might be called "active"  tension and "potential" tension. Active tension could be defined as what acts on a large scale, affecting the mass of the hammer and how it behaves in a direct way. Potential tension is something that is in the felt itself, and can be adjusted so as to become active tension, under certain conditions and using certain techniques.

Active tension is what we can see and feel when we cut open hammers as in the photos in one of my previous posts, and I surmise (and I think this is a fairly commonly held opinion) that it is a large part of what gives a hammer its ability to a have a wider range of tonal gradient, because it allows for movement of fibers within the hammer in a dynamic way. I would expect Bacon felt hammers to spring open more than the Abel hammer I experimented with, partly because of what I think of as "heat set" in the Abel hammers, partly because the additional density of the Abel inhibits  movement of the fibers. I would be curious to see the results of heat pressing and cold pressing identical felt, without glue, everything else the same as a normal hammer pressing. What would each felt strip look like when removed from the press? That might tell us something, and would probably be a good promotional pair of photos for a hammer manufacturer. I would expect the cold pressed felt to come closer to its original shape, but how much closer would be interesting to know.

What is "heat set," and how permanent is it? I don't know, in analytic terms, what happens to the individual fibers, but I don't believe it is permanent, and in pragmatic terms it seems to be reversible by the process of needling (or by other processes, like "voice-gripping" and steam and chemical means). The individual fibers have not lost their memory, and continue to try to go back to their original shapes when no longer constrained - unless so much heat has been used that some internal transformation has taken place, which I don't believe to be the case based on experience with various felts. I don't know for sure, but it certainly seems reasonable to assume that the pressure and heat of the original felting processes would have as much effect on the integrity of the fibers as the same heat and pressure during pressing of the hammers. Granted, there is a more "global" pulling and squeezing together of fibers, but from the point of view of the individual fibers, the forces applied would be analogous to what they have undergone in the initial felting processes.

"Potential" tension is part and parcel of the individual fibers of the felt. In my conception, hammer felt itself contains within it tension and compression. That is, the individual fibers all have "memory" of the crimp shape they had originally, and are "trying" to get back to that shape. Their individual situations are fairly random, some being bent more than in the natural state, others being pulled straighter than they were. If they are "pulled" straight, they are "tense" and trying to become crimped again. If they are "pressed" into a greater degree of bending, they are trying to straighten again, pushing outward. The former is tension, the latter compression, and the two are operating against one another within the matrix of the larger body of felt. This gives felt its "springiness." The forces of the individual fibers are minute in isolation, but taken all together become very significant.

The inherent tension and compression in a sheet of felt is somewhat altered when it is pressed into a hammer, as the large scale (millions of fibers being involved) action of forcing the felt around the core and fixing it in place causes considerable tension and compression, focusing these forces in different directions and creating a gradient in the large scale. Still, the initial tension and compression of the individual fibers continues to be there, altered somewhat, but it is a large part of the whole picture, and contributes a great deal to the behavior of the whole. The forces related to the individual fibers are magnified, as the fibers close to the core are more densely packed, but they continue to have the same memory and exert the same sort of force, even if constrained very tightly or stretched very taut.

How can it be that inserting needles could increase "active tension," when the needles go through the outer layers to get to the inner ones? In my conception, that has to do with the fact that the inner fibers are closer together, and needle work that penetrates deeply will "loosen the ties" of many more fibers than are either torn or "loosened" on the surface. (By "loosening" I mean that the felting ties, the connections between the scales of the individual fibers, are pulled apart, caused to be no longer effective in holding the fibers together - there is also some degree of tearing of fibers). So the inner fibers are able to "spring outward" and thereby cause additional tension on the surface, but also more tension in the interior of the hammer, as other "felting ties" are activated. Once the outer layers have been opened up from an initial needling, additional penetrations will have less of an effect, will tear less fibers, because the interlocking is looser (as we feel when doing additional needling later). Overall tension is no doubt reduced, but continues to be adequate to maintain a balance with a high degree of compression. The active tension compression gradient of the hammer is altered by these means.

I would add that needling technique can be a big factor here. That is why I insert needles deeply, insert being a key word, as opposed to stab. I believe that much stab voicing tends to penetrate more on the order of 5 - 6 mm rather than the 9 - 11 mm required, and that the result is a weakened outer tension and little effect toward the core of the hammer. The resulting sound tends to be pretty dead and colorless. Sometimes such a hammer can be revived with deep needling, but often not. I guess I should say that I have seen voicers who have a fairly precise "stab" technique that does penetrate to 10 mm or so consistently, though this "stab" is generally a bit slower than what I was describing as 5 - 6 mm penetration. I prefer a somewhat slower penetration, starting at the surface of the felt rather than moving when it hits the felt, as I am convinced it retains the integrity of the felting far better - and that is based on the experience of voicing the same sets of hammers over a period of a couple decades, and observing the results.

Well, I can see that this gets more and more convoluted to explain. As I try to make one part clearer, it requires expansion of another part, and the whole becomes less well organized. I think I will just leave it as it is, and hope that at least some of the concepts I have been trying to convey will come through with at least a little clarity. It is a mental model that has seemed to serve me well over the years, and to correspond pretty closely to what I experience when I work with hammers. It is only a model, not really verifiable. The techniques work, so I am not all that worried about whether my mental model is accurate.

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Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
"The true sign of intelligence is not knowledge, but imagination." - Einstein
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Original Message:
Sent: 04-02-2013 01:17
From: David Love
Subject: lacquer voicing

Fred:

No point in disputing felting versus fulling. There are several basic steps to wash, process, mix and interlock the felt create these thin little sheets which are stacked up on top of each other and then take this 12 inch or whatever thick pile of wool sheets and reduce it to a thinner and more dense piece of felt. The use of oscillating rollers, steam and heat in that later part also serves to further interlock the fibers. The result of good hammer felt making is a uniformly dense sheet of felt that is well interlocked and where the fibers are not damaged. The Weickert process is considered to be superior in terms of controlled and uniform density (over Bacon, VFG, "Japanese" methods): a good blend of both long and short fibers, health of the fiber when the process is over (not too many harsh chemicals that strip the felt of its natural substances), and the degree of interlocking. That's why the best hammer makers want it and use it. That's probably sufficient for our purposes however we wish to call the processes.

You need to be careful with straw man arguments here. You are misrepresenting what I have said before making an argument against it. I never said that tension was "absent" in a "hard pressed hammer". You can press a hammer very hard and it can have tension in it. The starting density of the sheet can impact how much stretching can be done but that is another issue. I said that the use of heat in the process of hammer making has an effect on tension, it lessens it, it does not increase it. The application of heat while the hammer is under tension alters the fibers structurally. But even with the use of heat there will likely be some tension, just less. Too much heat, however, and you can effectively destroy any or most tension. Since the voicing process itself (needling) reduces tension further, then starting with less leaves you with less to work with and it is more quickly dissipated.

If the debate is whether you want or need tension at all in a hammer, that's fine. You can argue that. I don't agree, but it's point that can be debated. A hammer without tension will still hit the string and impart energy. Neither am I suggesting you can't get acceptable results with hammers with less tension, or no tension for that matter. With some skill you can make just about anything work, even work fairly well, we do it all the time. I'm talking about what is desirable. I can't see a reason to reduce or eliminate tension in a hammer on purpose before you even start under pretty much any circumstances. Heat is the main culprit in that.

The interlocking fibers are, in fact, quite strong. Otherwise the felt will tear (or the molding will fracture if you are trying to shove it down into the caul without some prepressing). Poorer felt, in fact, can and does tear and the amount of stretching that can be done can be limited by that. Lack of space between the fibers does not insure that there is more tension (or less for that matter). You can have dense felt with no tension or not so dense felt with lots of tension. In terms of your experiment of cutting hammers apart, the less dense Bacon felt often opens the most in that experiment. Tension is not to do with the cauls, though they have a role in stretching the felt in the pressing process. The tension is in the felt and is only created through stretching. If the felt is not stretched there will be no tension. That's what tension is, it's the pulling of the felt in the opposite direction from which it has been or is being stretched. Once that stretching force is removed, there is no more tension. I don’t see how you can introduce stretching by needling. Needling releases (removes) tension.

I suppose that if you could expand the felt from underneath the hammer surface so that it stretched the outer layers then you could introduce tension into the outer layers of the hammer. But when you "needle" hammers, you needle from the outside in (generally). So when you say loosen the fibers (I assume you mean the outer fibers) to increase the tension that doesn't make sense to me. By "loosening" the fibers you are necessarily releasing or removing tension in the outer layers (they are no longer as stretched since you've now separated the fibers some. Just as when you loosen your elastic belt you remove tension from it. Your stomach may expand and reintroduce some tension back into your belt with, perhaps, some room to move now, but then you are saying that the release of tension of the outer layers that is constricting the hammer allows the hammer to expand and therefore introduces more tension into the outer fibers than was there in the first place. Not sure I buy that. You may well "open up" the hammer, an apt description, but you are not, as I see it, increasing tension. I suppose you could argue that deep needling expands the layers underneath more than the piercing of the outer layers removes tension that is either there or forming (or both) on the outside of the hammer. I can't comment on that. I'll have to rely on the scientists there. What I hear and the manner in which I see the hammers respond doesn't seem to suggest that however.

Rather, I think in that case you are simply making the hammer less dense, allowing it some room to compress thus introducing a degree of flexibility into an otherwise rigid body. Cleary that does work and is an important structural consideration when voicing hammers that have no tension but are simply too dense. We do this all the time with hammers that are too hard and have devised all kinds of enhanced interrogation techniques to accomplish this including: pliers, steam, water, dremel tools, needles, fabric softeners and vodka (such a waste). But creating a "density gradient" should not be mistaken for introducing tension that is somehow hidden in the hammer or confused with what happens in a tensioned hammer when you release tension by needling. A portion of the density in a hammer that is under tension is a function of the tension itself. As you needle and release the tension from the outer layers, the hammer becomes less dense. It's more complicated, of course, because in a tensioned hammer it seems that you can release tension in certain parts of the hammer to impact the density in other parts of the hammer. When you needle tensioned hammers low in the shoulders they can get brighter, or louder. There may be other reasons for that too which are beyond this discussion, already too long. But when the tension is gone, your only hope to replace the density lost by the loss of tension is to basically pack the hammer down--the ultimate fate of even the most tensioned hammer. That won't return the tension to the outer layers, it simply provides the next best substitute. That's why we should treat the tension in hammers as a limited commodity, something to preserve and be cautious with. Every needle stick lets air out of the balloon.

In many ways hammers with no tension that are simply density driven are easier and less sensitive to voicing mistakes. Hammers filled with lacquer, for example, can take all kinds of abuse: make then harder, make them softer, needles in the crown, you can get away with a lot. Good, well matched to the belly (doesn't always happen), tensioned hammers sound better, I think, more lively, more resilient, more open, more bounce, but they require more of a surgeon's touch. You can make a mistake and let all the air out of the balloon at once if you are too aggressive and not careful. Who knows, maybe that's the reason they are not valued as much.

I could be wrong, of course. Wouldn't be the first time (or the last). But I don't think so.

David Love
www.davidlovepianos.com

Hi David: Thanks for offering that and yes both processes are important to achieve the required density, uniformity and interlocking. It's slightly different from the information I'm getting from Jack Brand who is producing this Weickert felt but I'll check with him again to clarify. It may however be a technical issue and it's a bit tangential to the discussion. Suffice it to say that quality felt comes out in sheets at a uniform density that is well interlocked and then is sent to the hammer maker. The felt sheets come out at varying densities and are categorized and labeled that way. Different densities are used for different types of hammers. A concert grand hammer may well come from a more dense sheet, but not necessarily. The "hot pressing" used during the felt making process has a very different affect than hot pressing when the hammer is in the hammer press and the two shouldn't be confused or probably even called the same thing as hot pressing is really referred to generally in the hammer making process. The purpose of making a uniform and interlocked sheet is among other things, in order to be able to stretch it without it coming apart which will tension the felt over the crown of the hammer. Heating the felt while it is in the press can remove or lessen that tension. That's the down side of hot pressing, in my view, and has been a part of the discussion between Fred and me. David Love www.davidlovepianos.com
Original Message----- From: David Stanwood [mailto:noreply@egroups.ptg.org] Sent: Tuesday, April 02, 2013 3:30 AM To: David Love Subject: Voicing: RE:lacquer voicing Hi David, Just getting in on this discussion..... My wife Eleanor is a feltmaker and we've had a lot of experience visiting felt making factories and working with wool. In fact I'm making wool hats today... anyway..... The fulling process is a felting process just with more pressure. To make really hard felt the wool batts are first pressed between large hot plates and vibrated. The heat and water opens the scales on the fiber and the vibration interlocks the fibers. The hot/wet opened scales act like ratchets. Only so much density is achieved this initial "hardening" process like for damper felts, butt felts, and the like. To get higher density such as back check or hammer felt, higher pressure is needed in the "fulling" process. Hammer felt is fulled by pounding with powerful wood faced hammers in a fulling mill for many hours. The sheet comes out of the mill and is dried and pressed to take out unevenness in the fulling. So to some degree hammer felt sheets are hot pressed before they even make it to the hammer makers. The higher the quality of the manufacturing the less hot pressing of the sheets is needed after fulling to make the hammer makers specs. Density that is achieved by fulling has more fiber interlocking than density that is achieved by hot pressing. hope this helps. David Stanwood