Pianotech

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Original Message:
Sent: 6/25/2021 10:40:00 AM
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Nate, the optimal installation would include an undercover (or a back cover if its a vertical). Add a string cover if that doesn't seem sufficient.

------------------------------
Patrick Draine
Billerica MA
978-663-9690
------------------------------

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Nate,

The DC system is designed to work optimally between 35% and 65%RH. No, it cannot adequately counteract Sahara desert climate. They will need to augment it with room humidification or they are asking for trouble. Additionally, if any of these pianos are within their manufacturers warranty period, they may very well void that as well if they fail to adequately humidify.

I have added full covers to many of my grand installations with some good effect. Also as mentioned an undercover is effective.  However, tuning changes like this are not limited to the soundboard, but rather the entire structure is swelling and shrinking. Therefore the need to add some room humidity in the vicinity of the piano (just a few feet away). 

Iinstitutional situations are problematic due to the requirement of exchanging air on a specific minimal CFM. In the winter tbey are drawing in cold dry air and heating it up to 75 degrees making it wicked dry, and in the summer they're cycling in warm moist air and cooling it down making cool and moist...not so good. It's a no win situation unless they get on board with total inside and outside climate control AND tuning every 3 months. Unfortunately the ones who write the checks in these institutions typically don't get it (no matter what you say).  Have fun. 

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 06-25-2021 11:18
From: Patrick Draine
Subject: Dampp Chaser, extreme humidity changes?

Nate, the optimal installation would include an undercover (or a back cover if its a vertical). Add a string cover if that doesn't seem sufficient.

------------------------------
Patrick Draine
Billerica MA
978-663-9690

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Original Message:
Sent: 6/25/2021 6:15:00 PM
From: Peter Grey
Subject: RE: Dampp Chaser, extreme humidity changes?

Nate,

The DC system is designed to work optimally between 35% and 65%RH. No, it cannot adequately counteract Sahara desert climate. They will need to augment it with room humidification or they are asking for trouble. Additionally, if any of these pianos are within their manufacturers warranty period, they may very well void that as well if they fail to adequately humidify.

I have added full covers to many of my grand installations with some good effect. Also as mentioned an undercover is effective.  However, tuning changes like this are not limited to the soundboard, but rather the entire structure is swelling and shrinking. Therefore the need to add some room humidity in the vicinity of the piano (just a few feet away). 

Iinstitutional situations are problematic due to the requirement of exchanging air on a specific minimal CFM. In the winter tbey are drawing in cold dry air and heating it up to 75 degrees making it wicked dry, and in the summer they're cycling in warm moist air and cooling it down making cool and moist...not so good. It's a no win situation unless they get on board with total inside and outside climate control AND tuning every 3 months. Unfortunately the ones who write the checks in these institutions typically don't get it (no matter what you say).  Have fun. 

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 06-25-2021 11:18
From: Patrick Draine
Subject: Dampp Chaser, extreme humidity changes?

Nate, the optimal installation would include an undercover (or a back cover if its a vertical). Add a string cover if that doesn't seem sufficient.

------------------------------
Patrick Draine
Billerica MA
978-663-9690

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357
------------------------------

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, now, as lever technique changed, is no longer swinging, and is quite stable at pitch...was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days. 

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. String segment inequalities, and pin internal tension release after manipulation, offer a huge possibility for pitch movement by the tension equalization of the segments in time. This factor presents a much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my pianos, are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Fine tuning is accomplished with finessing the pin torsion and NSL tension and not turning the pin. Exact manipulation has been outlined in a previous thread.

------------------------------
Regards,

Jon Page
mailto:jonpage@comcast.net
http://www.pianocapecod.com
------------------------------

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. This, by the sheer fact that string segment inequalities offer a huge possibility for pitch movement by the shear equalization of the segments in time, presenting much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little tuning during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my recalcitrant pianos are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

hello Jim,
interesting point of view, however, how would you explain that pianos which i have tuned for many times, using the same technique, were going out of tune by a little before the DC unit was installed, are not going out of tune but by a fine hair after the install of the unit?  
I agree that hammer technique is extremely important but if you have a poorly constructed piano or poorly controlled environment in which the piano is, no amount of hammer technique is going to produce a tuning that is going to be stable for a long time.
Having said that, i have many customers whose pianos i tune on a frequent basis (once or twice yearly), some of which with a DC installed, most not, and most of those pianos drift in pitch no more than just a couple of cents.
Peter

------------------------------
Petrus Janssen
Peachtree City GA
678-416-8055
------------------------------

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. This, by the sheer fact that string segment inequalities offer a huge possibility for pitch movement by the shear equalization of the segments in time, presenting much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little tuning during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my recalcitrant pianos are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Jim,

What is your definition of a reasonable ambient climate?

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. String segment inequalities, and pin internal tension release after manipulation, offer a huge possibility for pitch movement by the tension equalization of the segments in time. This factor presents a much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my pianos, are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Peter,

I have to relate to my experience, which is mostly NE homes with any kind of modern heating system, including in floor heat (my own home). Some also have wood fired assist, but not too many. Other experiences have been a Sanctuary in big old episcopal flavor church. This building is heated for services, coasts at lower temps during the week, cranked for the geriatric customers on sunday, no AC in summer.  Heating in the homes is normal ambient home temps, maintained with run of the mill HVAC controls...nothing exotic...very few have controlled RH systems, but most are modern enough buildings where RH does not swing into the single digits (except for one that I know of, which is an antique home). So I am talking about pretty vanilla NE ambient conditions and swings. In my own house, we have french style windows, which are opened in all nice weather in the summer, so the living room is kind of like a screened porch in the summer, on nice days. Closed of course in rain, but hot days get pretty soggy here, no AC. I have a floor length cover on my piano, but the DC is disconnected. 

Most have DC's, since I had been recommending DC's and undercovers previously. All of them fluctuated more, irrespective whether they had a DC or not. Unisons floated well with the global pitch fluctuation. They all appear to be much more stable globally after I really honed minimal moving of the pins. Frequency of tuning, is some twice a year, but most once, none more than that, except the sanctuary. Maybe 3 for the sanctuary, and that is just to pretty it up for occasional concerts.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 06-26-2021 21:42
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Jim,

What is your definition of a reasonable ambient climate?

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. String segment inequalities, and pin internal tension release after manipulation, offer a huge possibility for pitch movement by the tension equalization of the segments in time. This factor presents a much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my pianos, are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Jim, I think you previously stated that you mostly tune your own rebuilds these days, the ones where you have changed things that affect stability. 
If I recall this correctly, it affects my understanding of your statement about stability being all about the tuner.

------------------------------
Cindy Strehlow, RPT
Urbana, IL
------------------------------

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. String segment inequalities, and pin internal tension release after manipulation, offer a huge possibility for pitch movement by the tension equalization of the segments in time. This factor presents a much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my pianos, are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Yes, Lucinda...gaining better global stability came while I combined my experience at the end of the lever, with analyzing and designing into my rebuilds why some pianos are easy to tune, while most are not. Also, following my various rebuilds allowed me, in visiting them over time, to see what was working and what wasn't in terms of rendering.  I now "see" the various forces; friction, elasticity , termination angles, counter bearing materials, felt/copolymer/brass combinations of materials, clearly while I mess with each pin.  I also perceive how pin torque effects string behaviour of each of the above parameters in tuning very clearly. I not only employ "design mind" during a rebuild now, but on each pin I manipulate. There are no longer any rendering surprises when tuning, and after stabilizing, I endeavour to move pins as little as possible.  Some pianos like a vintage Bechstein, which has a very mobile structure, I stabilize, then let it float for a few years. It will gradually drop bit by bit globally. I let it float, and after a couple of years, bring it back up to pitch, and re-stabilize.

Interesting thing in this is, I applied to teach a convention class on this very subject, front segment design from both the perspective of the tuner and rebuilder, and the greater minds that ponder such classes felt that this class would be of low interest...so it was rejected. Mostly, I think, because most tuners have no clue what is actually going on when they tune, and are working completely intuitively. Some might even find making this information conscious a threat to their tuning model.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 06-27-2021 07:44
From: Lucinda Strehlow
Subject: Dampp Chaser, extreme humidity changes?

Jim, I think you previously stated that you mostly tune your own rebuilds these days, the ones where you have changed things that affect stability.
If I recall this correctly, it affects my understanding of your statement about stability being all about the tuner.

------------------------------
Cindy Strehlow, RPT
Urbana, IL

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. String segment inequalities, and pin internal tension release after manipulation, offer a huge possibility for pitch movement by the tension equalization of the segments in time. This factor presents a much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my pianos, are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Jim wrote::
Interesting thing in this is, I applied to teach a convention class on this very subject, front segment design from both the perspective of the tuner and rebuilder, and the greater minds that ponder such classes felt that this class would be of low interest...so it was rejected. Mostly, I think, because most tuners have no clue what is actually going on when they tune, and are working completely intuitively. Some might even find making this information conscious a threat to their tuning model.

Hi Jim,
That is a gross mistake on the part of said "greater minds." Your class on action spread and elevation differential (my memory may have corrupted what you actually called it) is arguably MORE esoteric than anything to do with tuning. Tuning is how most of us earn most of our income. And yet the spread/elevation class was heavily attended, with many heavy-hitters present, and was brilliantly prepared and taught.

Sheesh!

Alan

------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------

Original Message:
Sent: 06-27-2021 08:56
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

Yes, Lucinda...gaining better global stability came while I combined my experience at the end of the lever, with analyzing and designing into my rebuilds why some pianos are easy to tune, while and most are not. Also, following my various rebuilds allowed me, in visiting them over time, to see what was working and what wasn't in terms of rendering.  I now "see" the various forces; friction, elasticity , termination angles, counter bearing materials, felt/copolymer/brass combinations of materials, clearly while I mess with each pin.  I also perceive how pin torque effects string behaviour of each of the above parameters in tuning very clearly. I not only employ "design mind" during a rebuild now, but on each pin I manipulate. There are no longer any rendering surprises when tuning, and after stabilizing, I endeavour to move pins as little as possible.  Some pianos like a vintage Bechstein, which has a very mobile structure, I stabilize, then let it float for a few years. It will gradually drop bit by bit globally. I let it float, and after a couple of years, bring it back up to pitch, and re-stabilize.

Interesting thing in this is, I applied to teach a convention class on this very subject, front segment design from both the perspective of the tuner and rebuilder, and the greater minds that ponder such classes felt that this class would be of low interest...so it was rejected. Mostly, I think, because most tuners have no clue what is actually going on when they tune, and are working completely intuitively. Some might even find making this information conscious a threat to their tuning model.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-27-2021 07:44
From: Lucinda Strehlow
Subject: Dampp Chaser, extreme humidity changes?

Jim, I think you previously stated that you mostly tune your own rebuilds these days, the ones where you have changed things that affect stability.
If I recall this correctly, it affects my understanding of your statement about stability being all about the tuner.

------------------------------
Cindy Strehlow, RPT
Urbana, IL

Original Message:
Sent: 06-26-2021 08:32
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I've been in the process of rethinking the DC installations.  I'm really not sure the DC does what we claim it does. On grand systems where I installed the undercover, at first, swings still occurred, until, frankly, my lever technique got to a point where the stability of the system was way better equalized in my tuning. So, I needed to ask myself, given, say a Forester, which can be hard to stabilize to begin with, was swinging 20c between tunings, got a DC/undercover, was still swinging, but, is no longer swinging, and is quite stable at pitch, was it me or the DC. I am afraid I am coming up in the side of my technique on this one, these days.

When I get a piano to a point where the pins have to be moved only in tiny increments, if at all, the swings, in a reasonable ambient climate don't seem to happen much.  So, I have been rethinking the whole DC thing, as I become one with the front segment tensions.

Regarding the two sides of the soundboard argument, ie, conditioning being different top and bottom sides, I don't think that correctly describes physically what is happening with the system. The system moderates the RH using temp of the soundboard. The soundboard will be relatively similar temp both top and bottom side. The conditioning happens, relative to temp, on a layer of air adjacent to the board called the "barrier layer". This conditioning layer is only molecules thick. Given a similar temp of the board top and bottom surfaces, the barrier layer top and bottom will function similarly. The question is, for me, whether that barrier layer can survive normal drafts and convective air movement, at the very low level the DC moderates it. And secondly, whether RH changes in the dimensions of the board, as we have discussed previously, don't seem to effect tension the way we assumed it did...the numbers don't work out to support this dimensional change/tension change explanation.

I really think pitch swing stability is more about the tuner, than DC systems. Its more about the tuner's relationship to the balance of front segment/SL tensions and pin untwisting after manipulation, than we realize. String segment inequalities, and pin internal tension release after manipulation, offer a huge possibility for pitch movement by the tension equalization of the segments in time. This factor presents a much larger potential for pitch swing than the inconclusive soundboard dimensional change explanation possibly can.

When a tuning is flying in at under an hour, using a statistically arrived at overpull function, on an ETD, the amount of tension imbalance between SL and NSL can be huge, in what the industry considers a well set pin. If a pin has been moved a decent amount, in a statistical overpull function, the overall tensions of the SL and NSL, relative to friction events and elasticity of the wire, will not be able to be perceived with the precision we think we are reading it. The only way to stabilize the system, is to get the pin position to a point where it is moved very little during tuning. That's been my experience for the last 3 or 4 years. Over the last few years, I really started to be able to both understand and perceive what all the forces acting on the front segment and friction points are. So, my pianos, are now stable, even over the last 1.5 years with no covid tunings, where previously, even with the DC/undercover, the pitch still swung...one has to ask why.  My answer is in equalization of the SL and NSL systems during a 2hr tuning, where the final pass is not statistically derived from an overpull function, and the pins have not been moved much if at all tuning to tuning..

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-25-2021 22:14
From: James Kelly
Subject: Dampp Chaser, extreme humidity changes?

Those readings are way outside the safety range and no Dampp Chaser is going to make much of an impact. Show them the booklet Dampp Chaser has that discusses and illustrates what the safety range is all about. More needs to be done with the central hvac design as well as central and local humidification and de-humidification. If they are serious about protecting their pianos they need to put them in a reasonable micro climate and understand a large percentage of a piano is wood. Wood reacts to humidity. Felt is affected by humidity, metal parts including piano wire react etc etc. Not knowing how the pianos are arranged around the building makes it hard to suggest solutions but at the very least better building humidification/de-humidification local area and room units close to the piano locations or in the same room .

Dampp=Chasers do great things but you can't expect them to solve building wide issues. Prolonged 5% humidity is bound to cause significant stress and damage- same goes with 60+. Here in South Carolina when you are in the 60-70-80 range you are inviting mold, mildew, rust. My favorite way of proving how bad it really is is to use data loggers 24x7 for a two week or more period. The graphs produced by a data logger will convince anyone there is a problem.




------------------------------
James Kelly
Owner- Fur Elise Piano Service
Pawleys Island SC
843-325-4357

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.  

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com
------------------------------

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.  

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have. 

There is one more thing I'll tackle in a subsequent post. 

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

To clarify, I am mostly talking about grands in my posts. I've stopped servicing uprights almost entirely, and really don't think about them much in my data. The few non DC uprights I service once a year, though, are stable as per the grands, but I have much less data re uprights.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I'm actually hopping over Jim's last post, just to try to keep these things in some sort of time line.  


Posted by Nate Rayburn on 6/25 -
Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

A slow Sunday perhaps? Why else go out of my way to step in it?
First, to revisit Nate's original post and question. From the outset, the real problem(s), having nothing really to do with humidity, are made manifest.
- We are left tantalizingly wondering at the nature of a client with multiple pianos in a commercial building.
- Are these new or rebuilt pianos?
- What is the nature of the relationship with the client that would lead them to imagine that a warranty tuning is a reasonable expectation?
- What level of enlightenment does the client possess to request A Dampp Chaser?
- 'Multiple' pianos would entail multiple Dampp Chasers.
But mostly:
- "… spun my wheels with them as hard as I politely can…"
How many 'multiple' pianos does this account have to have to coerce such deference?
As for paragraph #2 – I'll edit it to the salient questions:
Would a Dampp Chaser do more harm than good? …I'm interested to hear whether you guys think it's appropriate in this situation.
My response, completely apart from the fascinating discussion that has ensued since Nate's original posting, is: Yes, and No.
More harm than good, but not to the piano. To Nate. Given what we can assess of this client, their expectations will not be met, and they will blame Nate. For that reason, simply complying with the request is, in fact, inappropriate.

But my trouble making is what follows:
This thread bifurcated into two interesting sub-threads, each of which is deserving of its own focus –
   - The mechanics and effectiveness of the DamppChaser system
      o A sub-thread to this would be our obligation to frame such discussions in a way that does not gratuitously undermine the reputation of a supplier that has           demonstrated years of support to both the trade and improvements to the product.
   - The function of front-segment mechanics in tuning stability - providing links or citation to previous discussion would be helpful.

Trouble:  I'm starting two threads, once on each of the above topics.  If there's genuine interest in expanding on these, or citing previous information, this would hopefully make it easier to find, leaving us freeer to follow up on Nate's specifics.


------------------------------
David Skolnik [RPT]
Hastings-on-Hudson NY
917-589-2625
------------------------------

Original Message:
Sent: 06-27-2021 13:20
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

To clarify, I am mostly talking about grands in my posts. I've stopped servicing uprights almost entirely, and really don't think about them much in my data. The few non DC uprights I service once a year, though, are stable as per the grands, but I have much less data re uprights.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385
------------------------------

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

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

Original Message:
Sent: 06-28-2021 09:50
From: Gannon Rhinehart
Subject: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

My experience is similar to Peter’s. I’m also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn’t work, in my experience. I don’t see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385
------------------------------

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user
------------------------------

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don’t see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user
------------------------------

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user
------------------------------

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn’t seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can’t argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven’t heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I’ve missed it, I haven’t seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio’s meticulous attention to tuning technique but I don’t look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven’t seen anyone gainsay it. Anyway, if that isn’t right, I would like to know where I’m going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user
------------------------------

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Robert, you're right about the unison drift caused by rotation of the bridge. It was covered somewhere in last century's PTJ.

As for people unplugging systems. Make it difficult and intentional. Cover the plug with the child proofing outlet plug cover. Usually available in the kids section of the department store.

------------------------------
Larry Messerly, RPT
Bringing Harmony to Homes
www.lacrossepianotuning.com
ljmesserly@gmail.com
928-899-7292
------------------------------

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Actually, Jim, I don’t speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn’t a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn’t even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn’t happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can’t stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can’t see why this is an exotic explanation.
Don’t worry about tuning technique. Don’t even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can’t wait. Many people can and they live through the rough patches. Some people address humidity control. I’m all for that as you probably know by now. Finally, I’m also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes. 

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Here's a different thought on the subject of the efficacy of the DC, or more specifically, on the dynamics of Temperature vs RH in piano pitch migration.  

Temperature and RH are both highly interactive in normal ambient conditions. Because they are interactive, we assume, that they are both involved in the pitch migration issue. We assume that when one changes, say Temp, RH, which migrates with temp, is at fault...possibly conflating what parameter is having what effect. We don't actually know if they are both implicated. Temperature, has a huge effect on wire expansion/contraction. RH, has effects on the wood portion of the structure, but not on the wire. 

It would be informative to take a piano, enclose it in a precisely controlled environmental room, and observe what happens to the tuning drift, if temperature is maintained while RH is shifted. Vice a versa, if RH is maintained, but temperature is shifted, how would that effect pitch drift. It would be tricky to do this, as temp effect RH effect each other, but in an experimentally controlled lab room, I think temp and RH isolation could be pulled off.  I would be interested to see what parameter was responsible for what effect.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 07-02-2021 22:17
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes.

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Jim,

Add to this a laser pointer device of some sort attached to the top surface of the bridge (maybe several of them in different places) directed toward the ceiling to record the movement (If any) of the bridge. This arrangement would leverage any rotation (etc) and it's progress could be marked on the ceiling relative to the position of the piano underneath (perhaps draw lines parallel to the length of the piano to make it easier to chart what is actually happening), making a dot every few days or whatever.

I would think that if any rotation is happening this would be a way to capture it. If the bridge simplynmoves straight up and down, it would show no movement on the ceiling. 

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 07-03-2021 10:51
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

Here's a different thought on the subject of the efficacy of the DC, or more specifically, on the dynamics of Temperature vs RH in piano pitch migration.

Temperature and RH are both highly interactive in normal ambient conditions. Because they are interactive, we assume, that they are both involved in the pitch migration issue. We assume that when one changes, say Temp, RH, which migrates with temp, is at fault...possibly conflating what parameter is having what effect. We don't actually know if they are both implicated. Temperature, has a huge effect on wire expansion/contraction. RH, has effects on the wood portion of the structure, but not on the wire.

It would be informative to take a piano, enclose it in a precisely controlled environmental room, and observe what happens to the tuning drift, if temperature is maintained while RH is shifted. Vice a versa, if RH is maintained, but temperature is shifted, how would that effect pitch drift. It would be tricky to do this, as temp effect RH effect each other, but in an experimentally controlled lab room, I think temp and RH isolation could be pulled off.  I would be interested to see what parameter was responsible for what effect.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 22:17
From: Jim Ialeggio
Subject: Dampp Chaser, extreme humidity changes?

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes.

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I’ll just have to agree to disagree, Jim. I haven’t kept a quantitative record of pitch change, so I have to take my own idea as anecdotal at this point. I’m going to have to make exact measurements over time, which will take, well, time. My shop is mostly decommissioned these days and I no longer have a piano in it, so I’ll have to find a guinea pig. I would encourage others to take measurements of pitch across unisons at different points in the scale and at extremes of humidity. If you have a piano in your shop that you can use as a test subject, tune it and then measure and record the pitches of the notes you have selected. DON”T tune the piano again. That way you can eliminate any tuner manipulation that Jim suggests is efficacious. After your initial tuning, you have the piano at A440 (the exact pitch is not important). Measure all the As to find your baseline to compare future overall pitch change. Keep written records of humidity levels and take measurements at your selected notes when the piano is at the extremes.

BTW, many people, even piano technicians, talk about how dry it is in Arizona but Arizona does not have a uniform climate. People are generally surprised to hear that dehumidification could be needed. One misconception is that the weather outside is the same as in one’s house. We are usually modifying outside conditions to make it comfortable inside. Although we are in a desert here in Tucson and our official rainfall to date for 2021 is 1.3”, I measured the humidity in my backyard an hour ago. It was 65% and 81 degrees. In my shop it was 52% and 77 degrees. It has been 5 years since I completely switched from evaporative cooling to air conditioning. If I were running an evaporative cooler right now, the humidity inside would be in excess of 80%.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 10:18:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes. 

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Pitch (tension) migration, RH, air temp, string segments; it gets very complicated and seemingly fluid. I think there's also a "climate vs weather" dynamic as well. While air temperature and RH are linked, the air temp is volatile, it can be effected my many means and has immediate effects on the strings. Try placing your index finger on an A4 string for just 5 seconds and hear the immediate effect on the pitch. A 3 degree change in room temp will make a noticeable change in pitch much quicker than it will affect the RH or water content in the board. When a hall is filled with people both the temp and RH are likely to rise, the net effect is for the pitch to go down.
This also raises the question of the effect of opening a piano up for tuning, say on a vertical with a dehumidifier, letting the warm air out-tuning the instrument-then closing it back up where it reheats. Oops. Same goes for grands that sit with the lid down or even covered and then opened up to be played. 
There have been two thorough explanations in recent threads about how energy transfers from the strings into the plate, supports, and cabinet. I wonder, what is the effect of RH on the supports and cabinets, and do they impinge on the soundboard as they react to RH changes? 
Bob mentioned "the rolling of the bridge is something like the tacking of a ship." Actually I've thought about it perhaps as "pitch and yaw" (no pun intended) and wondered if tension migration might be due to a ratcheting effect as the bridge rolls back and forth over a period of time transferring the energy from one side of the bridge to the other. And a seesaw effect as the bridge goes down in the middle and up at either end. 
Inquiring minds want to know.

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129
------------------------------

Original Message:
Sent: 07-03-2021 11:08
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I'll just have to agree to disagree, Jim. I haven't kept a quantitative record of pitch change, so I have to take my own idea as anecdotal at this point. I'm going to have to make exact measurements over time, which will take, well, time. My shop is mostly decommissioned these days and I no longer have a piano in it, so I'll have to find a guinea pig. I would encourage others to take measurements of pitch across unisons at different points in the scale and at extremes of humidity. If you have a piano in your shop that you can use as a test subject, tune it and then measure and record the pitches of the notes you have selected. DON"T tune the piano again. That way you can eliminate any tuner manipulation that Jim suggests is efficacious. After your initial tuning, you have the piano at A440 (the exact pitch is not important). Measure all the As to find your baseline to compare future overall pitch change. Keep written records of humidity levels and take measurements at your selected notes when the piano is at the extremes.

BTW, many people, even piano technicians, talk about how dry it is in Arizona but Arizona does not have a uniform climate. People are generally surprised to hear that dehumidification could be needed. One misconception is that the weather outside is the same as in one's house. We are usually modifying outside conditions to make it comfortable inside. Although we are in a desert here in Tucson and our official rainfall to date for 2021 is 1.3", I measured the humidity in my backyard an hour ago. It was 65% and 81 degrees. In my shop it was 52% and 77 degrees. It has been 5 years since I completely switched from evaporative cooling to air conditioning. If I were running an evaporative cooler right now, the humidity inside would be in excess of 80%.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 10:18:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes.

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Bob,   My view is anecdotal too at this point.  Actually teasing out the specifics at this level becomes almost impossible to prove one way or the other, or whether both are in their own ways correct.  I only entered the conversation, because piano' that I previously had on DC's which still drifted, have mostly stopped drifting, after I started tuning differently. But who knows, maybe that's anecdotal too. 

One thing I will do in the shop, is try and figure a way to directly measure the pitch and yaw you and Steve mention. Though, finding a reliable reference may be impossible...have to think on it.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
------------------------------

Original Message:
Sent: 07-03-2021 13:55
From: Steven Rosenthal
Subject: Dampp Chaser, extreme humidity changes?

Pitch (tension) migration, RH, air temp, string segments; it gets very complicated and seemingly fluid. I think there's also a "climate vs weather" dynamic as well. While air temperature and RH are linked, the air temp is volatile, it can be effected my many means and has immediate effects on the strings. Try placing your index finger on an A4 string for just 5 seconds and hear the immediate effect on the pitch. A 3 degree change in room temp will make a noticeable change in pitch much quicker than it will affect the RH or water content in the board. When a hall is filled with people both the temp and RH are likely to rise, the net effect is for the pitch to go down.
This also raises the question of the effect of opening a piano up for tuning, say on a vertical with a dehumidifier, letting the warm air out-tuning the instrument-then closing it back up where it reheats. Oops. Same goes for grands that sit with the lid down or even covered and then opened up to be played.
There have been two thorough explanations in recent threads about how energy transfers from the strings into the plate, supports, and cabinet. I wonder, what is the effect of RH on the supports and cabinets, and do they impinge on the soundboard as they react to RH changes?
Bob mentioned "the rolling of the bridge is something like the tacking of a ship." Actually I've thought about it perhaps as "pitch and yaw" (no pun intended) and wondered if tension migration might be due to a ratcheting effect as the bridge rolls back and forth over a period of time transferring the energy from one side of the bridge to the other. And a seesaw effect as the bridge goes down in the middle and up at either end.
Inquiring minds want to know.

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 07-03-2021 11:08
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I'll just have to agree to disagree, Jim. I haven't kept a quantitative record of pitch change, so I have to take my own idea as anecdotal at this point. I'm going to have to make exact measurements over time, which will take, well, time. My shop is mostly decommissioned these days and I no longer have a piano in it, so I'll have to find a guinea pig. I would encourage others to take measurements of pitch across unisons at different points in the scale and at extremes of humidity. If you have a piano in your shop that you can use as a test subject, tune it and then measure and record the pitches of the notes you have selected. DON"T tune the piano again. That way you can eliminate any tuner manipulation that Jim suggests is efficacious. After your initial tuning, you have the piano at A440 (the exact pitch is not important). Measure all the As to find your baseline to compare future overall pitch change. Keep written records of humidity levels and take measurements at your selected notes when the piano is at the extremes.

BTW, many people, even piano technicians, talk about how dry it is in Arizona but Arizona does not have a uniform climate. People are generally surprised to hear that dehumidification could be needed. One misconception is that the weather outside is the same as in one's house. We are usually modifying outside conditions to make it comfortable inside. Although we are in a desert here in Tucson and our official rainfall to date for 2021 is 1.3", I measured the humidity in my backyard an hour ago. It was 65% and 81 degrees. In my shop it was 52% and 77 degrees. It has been 5 years since I completely switched from evaporative cooling to air conditioning. If I were running an evaporative cooler right now, the humidity inside would be in excess of 80%.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 10:18:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes.

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I really, really dislike the term "bridge roll." Years ago it seemed it was most often invoked when a long neglected grand has a major pitch raise and the tone (sustain, etc.) has reportedly cratered. There's just so many factors (the owner loved the purring unisons before the service appointment, for example). 
Much greater string tension ​might deflect the bridge downward in a weak board/rib configuration, resulting in insufficient bearing, etc., and degraded sustain etc. But I don't thing "rolling" has anything to do with it.

------------------------------
Patrick Draine
Billerica MA
978-663-9690
------------------------------

Original Message:
Sent: 07-03-2021 13:55
From: Steven Rosenthal
Subject: Dampp Chaser, extreme humidity changes?

Pitch (tension) migration, RH, air temp, string segments; it gets very complicated and seemingly fluid. I think there's also a "climate vs weather" dynamic as well. While air temperature and RH are linked, the air temp is volatile, it can be effected my many means and has immediate effects on the strings. Try placing your index finger on an A4 string for just 5 seconds and hear the immediate effect on the pitch. A 3 degree change in room temp will make a noticeable change in pitch much quicker than it will affect the RH or water content in the board. When a hall is filled with people both the temp and RH are likely to rise, the net effect is for the pitch to go down.
This also raises the question of the effect of opening a piano up for tuning, say on a vertical with a dehumidifier, letting the warm air out-tuning the instrument-then closing it back up where it reheats. Oops. Same goes for grands that sit with the lid down or even covered and then opened up to be played.
There have been two thorough explanations in recent threads about how energy transfers from the strings into the plate, supports, and cabinet. I wonder, what is the effect of RH on the supports and cabinets, and do they impinge on the soundboard as they react to RH changes?
Bob mentioned "the rolling of the bridge is something like the tacking of a ship." Actually I've thought about it perhaps as "pitch and yaw" (no pun intended) and wondered if tension migration might be due to a ratcheting effect as the bridge rolls back and forth over a period of time transferring the energy from one side of the bridge to the other. And a seesaw effect as the bridge goes down in the middle and up at either end.
Inquiring minds want to know.

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 07-03-2021 11:08
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I'll just have to agree to disagree, Jim. I haven't kept a quantitative record of pitch change, so I have to take my own idea as anecdotal at this point. I'm going to have to make exact measurements over time, which will take, well, time. My shop is mostly decommissioned these days and I no longer have a piano in it, so I'll have to find a guinea pig. I would encourage others to take measurements of pitch across unisons at different points in the scale and at extremes of humidity. If you have a piano in your shop that you can use as a test subject, tune it and then measure and record the pitches of the notes you have selected. DON"T tune the piano again. That way you can eliminate any tuner manipulation that Jim suggests is efficacious. After your initial tuning, you have the piano at A440 (the exact pitch is not important). Measure all the As to find your baseline to compare future overall pitch change. Keep written records of humidity levels and take measurements at your selected notes when the piano is at the extremes.

BTW, many people, even piano technicians, talk about how dry it is in Arizona but Arizona does not have a uniform climate. People are generally surprised to hear that dehumidification could be needed. One misconception is that the weather outside is the same as in one's house. We are usually modifying outside conditions to make it comfortable inside. Although we are in a desert here in Tucson and our official rainfall to date for 2021 is 1.3", I measured the humidity in my backyard an hour ago. It was 65% and 81 degrees. In my shop it was 52% and 77 degrees. It has been 5 years since I completely switched from evaporative cooling to air conditioning. If I were running an evaporative cooler right now, the humidity inside would be in excess of 80%.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 10:18:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

I respectfully am not buying it. Main reason being the same reason that the rise and fall doesn't convince me...that being, that in order to effect the changes we see, the rise or fall has to be a large vertical distance that just doesn't happen...this is where the numbers don't work out. Along those same lines, if there were a discrepancy in how much the 3 strings deviated from each other because of their distance from the axis, the sheer rotational and vertical discrepancy between the strings would have to be of a distance that is simply not possible. The numbers point to a very large vertical distance required to effect said changes.

On the other hand, looking at it from the front segment part of the system, the left string (grand) being hyper responsive to changes, is also the string with the shortest front scale length. On that note, the tuner must find the pin's rotational position to a much finer tolerance than the middle and right string. Both the middle and right string have longer NSL's, more elasticity in the NSL length, and thus more tolerance in where the tuner can place the rotational position of the pin and still be stable. The left pin is just less forgiving in pin position, and will always react first to changes in the system's equilibrium.

Regarding the rotation of the bridge, rotation in the tenor would have to be linearly along the length of the tenor bridge, becasue of the angle the unisons sit at in the tenor. Its kind of like the tenor bridge would be doing an end to end "wheelie"...which is not something that is physically plausible. While the tenor is doing a "wheelie", at the same time, in the first capo, as the board rises, and supposedly rotates towards the hitch, DB also increases. Because of the curve in the bridge at that location, whatever backwards rotation might be imagined, would be counteracted by the increased DB forcing the bridge which causes first capo area of  the bridge to rotate forward towards the player. Increased DB causes the first capo area to collapses into the convex side of the bridge curve. This I have seen and experimented with many times in the shop, as I tried to understand how the shape of the bridge creates so many problems for us. So there would be (at least) two rotational forces, and they would counteract each other. This means while the tenor does a wheelie backwards along the length of the tenor bridge, the first capo, which is attached to the tenor in wheelie mode,  rotates in a different rotation angle relative to the tenor...meaning they go in different directions. WHile the bridge does experience serpentine squirming under load, the two sections are further restraining each other from the major vertical movement necessary to achieve said changes.

That's why I call it an exotic explantation. I really think that though the system is complicated, the answer is and has been right under our noses all along. The front segment physically, already contains all the energy needed to effect the changes we see all the time.

--------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 18:22
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

Actually, Jim, I don't speak of one axis of rotation for the whole bridge. Anywhere I look on the bridges, I see that the notches are cut to be parallel to the opposite string terminations. The tenor part of the long bridge (where the strings played the most are located) is not exactly, but pretty much lying in a diagonal line; the same can be said for the lower treble section (at a less severely diagonal angle) and for the upper treble section (which gets closer to being parallel to the string terminations). There isn't a myriad of axes of rotation. But as the crowned soundboard expands when it takes on moisture, it has nowhere to go but up. I have always seen a rise in pitch when the humidity rises. The piano doesn't even have to be tuned. When the humidity goes back down, the strings return pretty much to where they were in the first place. The area of the string affected first when the soundboard expands is the speaking length, not the front string segments, which are farthest away from the soundboard. If the bridge were uniformly parallel to the upper string terminations, as the strings pull on the bridge, the bridge would rotate or roll equally for all strings of any given unison and there would be no appreciable difference in pitch change across that unison. This doesn't happen. The rolling of the bridge is something like the tacking of a ship. The increased force on the strings on a diagonally mounted bridge causes the bridge to roll in a direction different from the direction of pull of the strings. And the right and left strings of a given unison are always at a different pitch (sometimes to a distressing degree). The right and left strings are also at different distances from the axis of rotation of the bridge at whatever point you select. As the bridge rotates all three strings can't stay at the same pitch. (This becomes less obvious in the top section, where the bridge approaches the perpendicular to the string length.) I may just be obtuse but I can't see why this is an exotic explanation.
Don't worry about tuning technique. Don't even worry about tuning the piano at all. The piano will sound better again once the humidity returns to its previous level. Granted that sometimes you just can't wait. Many people can and they live through the rough patches. Some people address humidity control. I'm all for that as you probably know by now. Finally, I'm also all for the careful attention to tuning technique that Jim has set forth, no matter what the situation.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/2/2021 3:28:00 PM
From: Jim Ialeggio
Subject: RE: Dampp Chaser, extreme humidity changes?

<The strings of a unison, being different distances from the axis of rotation, react differently.

Bob...you speak of the axis of rotation as being a single axis. The sweeping bridge presents a myriad of axes, as there is no common angle relative to the strings in the entire 88 note compass. So there are 88 axes of rotation. The beam, while capable of flexing is going to trend the forces. It is incapable of flexing per unison, and certainly incapable of differential flexing within a unison. SO I see this as an exotic and improbable explanation for the phenomenon.

Instead, if one looks at the front segment, especially in a grand, there are 3 very clear front segment lengths per unison, one short, one medium and one long. Elasticity will vary per length of the front segments. This means, because of string elasticity, and because of varying NSL lengths, and friction, each of those strings of the unison, even if set with absolutely perfect tension balance relative to the SL, will still have different tension thresholds beyond which their strings can pull wire into the NSL, or release it to the SL. This exchange of wire over the friction points, offers a huge and utterly rational mechanism for changing SP pitch. On the other hand, the numbers simply do not support the possibility on other exotic explanations having the sheer degree of effect we routinely see occuring.

------------------------------
Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I think you have balanced view of the DC system Bob, and I agree that it shouldn't be a substitute for tunings. Unfortunately, in my opinion, the main reason people have one installed is so they don't have to have the piano tuned as often and I think that's the wrong reason to install one. It may prevent the tuning from going "wacko" but it still needs regular tunings to sound good.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user
------------------------------

Original Message:
Sent: 07-02-2021 10:50
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I follow you, Scott. One of my main concerns in making any institutional installation is how to keep the D-Chaser plugged in. I always emphasize the point that someone needs to be responsible for monitoring the system, not only to water it but to make sure that it always has power. Where any number of people or groups have access to a room, it is inevitable that someone will eventually need an electrical outlet or need to move the piano. The chances of the D-Chaser getting reconnected are less than average.
But in my experience the good that the D-Chaser does for pianos outweighs the possible pitfalls. And there are plenty of pitfalls including improper installation. Although Dampp-Chaser offers excellent tutorials and installation instructions, I have seen such things as humidistats installed directly under dehumidifier rods and humidifiers without moisture distributions. The technician has to pick the battles and decline an installation if success doesn't seem probable. In any case, there is no call for a blanket endorsement or dismissal of the use of a Damp-Chaser system. Someone suggested the usefulness of a room humidifier to supplement the D-Chaser. I can't argue with that but not all room humidifiers are equal. A humidifier that evaporates water into the air is superior to one that emits water particles that can condense on metal surfaces. How easy is it to control the amount of humidification? How often does it need to be cleaned? How often does it need water? BTW, I saw one post to this thread suggesting that Dampp-Chaser humidifiers needed to be watered every day. That is not true. My own grand calls for water about every 7 days and I haven't heard of anyone needing it more often.

Another aspect of this thread has emphasized the use of D-Chasers to stabilize tuning. My primary concern has always been to preserve the integrity of the soundboard. Humidity change stresses glue joints and the cellular structure of the wood. I must be in the minority because, unless I've missed it, I haven't seen anything in this thread that supports that line of reasoning. I appreciate Jim Ialeggio's meticulous attention to tuning technique but I don't look at the Dampp-Chaser as a substitute tor tuning needs. One of the symptoms of humidity change that I have noticed is that unisons go out of tune. In a class by Klaus Fenner on tuning stability, he said that pitch needed to be raised by about 60% of a semitone to pull the string across the bridge and that the effect of a big pitch raise or soundboard expansion or contraction was to roll the bridge around its axis. The strings of a unison, being different distances from the axis of rotation, react differently. I have mentioned it before on this forum. It has been met with silence but so far I haven't seen anyone gainsay it. Anyway, if that isn't right, I would like to know where I'm going wrong.

Bob Anderson, RPT
Tucson, AZ


Original Message:
Sent: 7/1/2021 8:26:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

Bob - One of the main things I was referring to was the system getting unplugged. The situations I've seen this happen are where the piano is moved around.

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 07-01-2021 07:59
From: Robert Anderson
Subject: Dampp Chaser, extreme humidity changes?

I would never install a D-chaser without a Smart Bracket, Scott. Unless the piano is in an area that never needs dehumidification, I don't see how the D-chaser could be useless or cause harm. The dehumidifier will activate if the humidity is too high no matter what. If there is no water in the tank, the Smart Bracket will turn off the humidifier.

Bob Anderson, RPT
Tucson,AZ


Original Message:
Sent: 6/29/2021 1:29:00 PM
From: Scott Kerns
Subject: RE: Dampp Chaser, extreme humidity changes?

"Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained." Joe Wiencek

Yes, I think that's exactly the point with the DC system. It should first be determined, before installation, if there is someone who will take responsibility for maintaining it. Most all of the systems I see are not maintained or sporadically maintained and therefore are at the least useless and at the most detrimental to the piano. 

------------------------------
"That Tuning Guy"
Scott Kerns
www.thattuningguy.com
PianoMeter, TuneLab & OnlyPure user

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Joe,

I agree wholeheartedly that counting on janitors, faculty members and the like to maintain humidity control systems is a losing proposition. However, I have a crew of students who are paid by The Institute and whose time sheets are approved by me who are very good at doing this job. We are normally able to monitor these systems at least two or three times per week, which generally prevents the pianos from getting so dry that the pad light comes on.

We have just added room humidifiers to a couple of applications where the pianos have digital technology, and the manufacturer said no water tanks. We have humidistats and drying rods on those pianos, and will rely on the room humidifiers for the other side of the equation.

At this time of year, humidity swings are often 50% or more within a single day. So the variation is not just seasonal.

Best, 

Alan

------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------

Original Message:
Sent: 06-29-2021 13:09
From: Joe Wiencek
Subject: Dampp Chaser, extreme humidity changes?

My experience is similar to Peter's. I'm also in the NE. Very effective for stabilizing uprights in particular. (My wife asked me to tune our upright, and I bought myself some time by installing a DC and waiting the stabilizing period, heh heh!)

At the University I work, there are several DC units on various pianos, mostly on Steinway grands, only 2 have undercovers. The buildings are supposedly HVAC controlled, but there is a lot of variation from one room to the next, and from season to season. Several rooms have 2 pianos, and there have been occasions where one of those pianos does not have a DC unit, and the other one does. I have witnessed a huge variation in pitch stability between the two, which gets brought back within much tighter limits when a DC unit is installed on the deficient piano. As I am the one filling the pianos, I make sure they are maintained.

Letting the maintenance fall to janitors or students doesn't work, in my experience. I don't see how one could make a statement about the efficacy of DC if they are not being properly maintained. And certainly controlling room humidity levels is paramount for any stabilizing of wooden structures.

Joe Wiencek
NYC


Original Message:
Sent: 6/28/2021 9:50:00 AM
From: Gannon Rhinehart
Subject: RE: Dampp Chaser, extreme humidity changes?

For the last 12 years I have had a tuning contract for 60 pianos at a University.
A different company has the repair and rebuilding contract. A few years ago they started installing Dammp-Chasers so far on about half of them.

My experience is that the ones with the Dammp-Chasers have been more out of tune.
Not because of the systems but because they are counting on the janitors to keep them filled.
An occationally filled system is worse than no system.

The only thing that has made a difference for me and how out of tune they are the next go around is very much like Jim, how much time I take to stabilize the tunings. For me that means bringing it to pitch and then going back through it a second time and fine tuning it.
But being cheap pianos when they were new that now have been abused as practice room pianos for 40 years not much is going to really help.

------------------------------
Gannon Rhinehart
Santa Fe NM
505-692-8385

Original Message:
Sent: 06-27-2021 12:41
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

My experience has been slightly different in that I have found HUGE improvement in stability in virtually (repeat virtually...not 100% universal) every upright piano I have installed a system in (provided of course that it is maintained as designed and not attempting to compensate for 40% - 80% swing range in humidity).

In grands (due to their more open nature) the control is far less effective. Other compensatory measures must be taken to enhance its effectiveness as has already been discussed. However I have observed excellent results by adding a room humidifier in the vicinity of the piano. Again, if regularly attended to this can make a HUGE difference overall.

Additionally, if in discussion with the client, I detect that 1) They are not likely to maintain the system as needed, and/or 2) They tend to view the system as a panacea to solve all their piano problems (including tuning), or 3) some other disqualifying factor, I will not move forward with recommending the system's installation. I have learned pretty much to pick my battles,  and this is one I choose not to have.

There is one more thing I'll tackle in a subsequent post.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-27-2021 09:41
From: David Weiss
Subject: Dampp Chaser, extreme humidity changes?

Jim, thank you for the excellent post.  Lever technique and tuning pin movement are critical.
I once was a proponent of PLS but now I am reluctant to recommend one.  Very simply, I don't see significant  changes in stability after installing a system.  Sometimes I see no change at all, other times it is minimal.
I do often see significant changes in stability when a client does room or whole house humidity control.  However most people won't take that step because it is too cumbersome.

David

David Weiss
Registered Piano Technician
(434) 823-9733
davidweisspiano@gmail.com
www.davidweisspiano.com

------------------------------
David Weiss
Charlottesville VA
434-823-9733
davidweisspiano@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean. 

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

I'm not really into the "internet of things" concept but keeping the DC system filled seems like a good application of bluetooth tech. Even for retro fitting, one can get a bluetooth camera at a fairly low cost. There are wireless water level sensors too. https://www.amazon.com/Ready-Internet-Ultrasonic-Water-Liquid/dp/B07DY5NK97/ref=sr_1_66
Maybe DC will add the feature?

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129
------------------------------

Original Message:
Sent: 06-29-2021 10:39
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Steven,

Maybe they will add that feature, someday...

The idea of Bluetooth monitoring of DC systems (especially useful in places where there are dozens of them in use) has been presented to the Dampp-Chaser folks multiple times. So far, no dice.

The pandemic makes this idea even more appealing, eliminating as it does the need to enter rooms in order to find out if the system is thirsty.

Alan

------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------

Original Message:
Sent: 06-30-2021 15:36
From: Steven Rosenthal
Subject: Dampp Chaser, extreme humidity changes?

I'm not really into the "internet of things" concept but keeping the DC system filled seems like a good application of bluetooth tech. Even for retro fitting, one can get a bluetooth camera at a fairly low cost. There are wireless water level sensors too. https://www.amazon.com/Ready-Internet-Ultrasonic-Water-Liquid/dp/B07DY5NK97/ref=sr_1_66
Maybe DC will add the feature?

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 06-29-2021 10:39
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Hi, Alan,

While I totally agree that this would be a wonderful thing, I'm not sure that the technology is yet at a point at which it would be financially responsible for DC to try to incorporate it.

As you note...maybe someday.

Kind regards.

Horace





  Original Message


Original Message:
Sent: 6/30/2021 3:53:00 PM
From: Alan Eder
Subject: RE: Dampp Chaser, extreme humidity changes?

Steven,

Maybe they will add that feature, someday...

The idea of Bluetooth monitoring of DC systems (especially useful in places where there are dozens of them in use) has been presented to the Dampp-Chaser folks multiple times. So far, no dice.

The pandemic makes this idea even more appealing, eliminating as it does the need to enter rooms in order to find out if the system is thirsty.

Alan

------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------

Original Message:
Sent: 06-30-2021 15:36
From: Steven Rosenthal
Subject: Dampp Chaser, extreme humidity changes?

I'm not really into the "internet of things" concept but keeping the DC system filled seems like a good application of bluetooth tech. Even for retro fitting, one can get a bluetooth camera at a fairly low cost. There are wireless water level sensors too. https://www.amazon.com/Ready-Internet-Ultrasonic-Water-Liquid/dp/B07DY5NK97/ref=sr_1_66
Maybe DC will add the feature?

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 06-29-2021 10:39
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Hi, Steven,

While I have misgivings about the "InternetofThings" (aka "IoT" ), there are places and applications where such technology can, if wisely and carefully implemented, be truly helpful. Nate's situation sounds like it might be one.

Since I'm currently on my mobile, and I'm a Luddite to begin with, I won't try to cut and paste from the Amazon page here; but will urge that folks looking to this kind of solution take a very careful read of the review of this product from Barry Boes, on the Amazon page.

Having set up a number of things like this in our home and shop, I can relate that Mr. Boes' thoughts on the complexity of actually getting devices like this (and the systems required for them to work as expected) running competently is not a project lightly undertaken. Here, in order to keep unwanted and difficult-to-secure traffic contained so that it doesn't contaminate the rest of our network, I eventually set up IPSEC on a separate logical network. The process has been both time-consuming and not all that cheap.

On net, I suspect that Nate's clients are not likely to spring for anything more than demanding "warranty" tunings...for which life is already far too short.

Kind regards.

Horace





  Original Message


Original Message:
Sent: 6/30/2021 3:37:00 PM
From: Steven Rosenthal
Subject: RE: Dampp Chaser, extreme humidity changes?

I'm not really into the "internet of things" concept but keeping the DC system filled seems like a good application of bluetooth tech. Even for retro fitting, one can get a bluetooth camera at a fairly low cost. There are wireless water level sensors too. https://www.amazon.com/Ready-Internet-Ultrasonic-Water-Liquid/dp/B07DY5NK97/ref=sr_1_66
Maybe DC will add the feature?

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129
------------------------------

Original Message:
Sent: 06-29-2021 10:39
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Well, how about the Begonia method. Put a potted plant next to the piano, when it needs watering so does the piano.

(Actually, since the DC has a warning light, it's not much of a step further for it to send a blip to one's computer/phone...)

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129
------------------------------

Original Message:
Sent: 06-30-2021 16:03
From: Horace Greeley
Subject: Dampp Chaser, extreme humidity changes?

Hi, Steven,

While I have misgivings about the "InternetofThings" (aka "IoT" ), there are places and applications where such technology can, if wisely and carefully implemented, be truly helpful. Nate's situation sounds like it might be one.

Since I'm currently on my mobile, and I'm a Luddite to begin with, I won't try to cut and paste from the Amazon page here; but will urge that folks looking to this kind of solution take a very careful read of the review of this product from Barry Boes, on the Amazon page.

Having set up a number of things like this in our home and shop, I can relate that Mr. Boes' thoughts on the complexity of actually getting devices like this (and the systems required for them to work as expected) running competently is not a project lightly undertaken. Here, in order to keep unwanted and difficult-to-secure traffic contained so that it doesn't contaminate the rest of our network, I eventually set up IPSEC on a separate logical network. The process has been both time-consuming and not all that cheap.

On net, I suspect that Nate's clients are not likely to spring for anything more than demanding "warranty" tunings...for which life is already far too short.

Kind regards.

Horace





  Original Message


Original Message:
Sent: 6/30/2021 3:37:00 PM
From: Steven Rosenthal
Subject: RE: Dampp Chaser, extreme humidity changes?

I'm not really into the "internet of things" concept but keeping the DC system filled seems like a good application of bluetooth tech. Even for retro fitting, one can get a bluetooth camera at a fairly low cost. There are wireless water level sensors too. https://www.amazon.com/Ready-Internet-Ultrasonic-Water-Liquid/dp/B07DY5NK97/ref=sr_1_66
Maybe DC will add the feature?

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 06-29-2021 10:39
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------

Many years ago I had one client that rigged up a system to keep the humidifier filled from his toilet (the tank part obviously). Precisely how he did it I have long forgotten, But the reason was because he would spend large swaths of time away from home and recognized the need to maintain the thing, thus he used his ingenuity to make it happen. 

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com
------------------------------

Original Message:
Sent: 06-30-2021 16:12
From: Steven Rosenthal
Subject: Dampp Chaser, extreme humidity changes?

Well, how about the Begonia method. Put a potted plant next to the piano, when it needs watering so does the piano.

(Actually, since the DC has a warning light, it's not much of a step further for it to send a blip to one's computer/phone...)

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 06-30-2021 16:03
From: Horace Greeley
Subject: Dampp Chaser, extreme humidity changes?

Hi, Steven,

While I have misgivings about the "InternetofThings" (aka "IoT" ), there are places and applications where such technology can, if wisely and carefully implemented, be truly helpful. Nate's situation sounds like it might be one.

Since I'm currently on my mobile, and I'm a Luddite to begin with, I won't try to cut and paste from the Amazon page here; but will urge that folks looking to this kind of solution take a very careful read of the review of this product from Barry Boes, on the Amazon page.

Having set up a number of things like this in our home and shop, I can relate that Mr. Boes' thoughts on the complexity of actually getting devices like this (and the systems required for them to work as expected) running competently is not a project lightly undertaken. Here, in order to keep unwanted and difficult-to-secure traffic contained so that it doesn't contaminate the rest of our network, I eventually set up IPSEC on a separate logical network. The process has been both time-consuming and not all that cheap.

On net, I suspect that Nate's clients are not likely to spring for anything more than demanding "warranty" tunings...for which life is already far too short.

Kind regards.

Horace





  Original Message


Original Message:
Sent: 6/30/2021 3:37:00 PM
From: Steven Rosenthal
Subject: RE: Dampp Chaser, extreme humidity changes?

I'm not really into the "internet of things" concept but keeping the DC system filled seems like a good application of bluetooth tech. Even for retro fitting, one can get a bluetooth camera at a fairly low cost. There are wireless water level sensors too. https://www.amazon.com/Ready-Internet-Ultrasonic-Water-Liquid/dp/B07DY5NK97/ref=sr_1_66
Maybe DC will add the feature?

------------------------------
Steven Rosenthal
Honolulu HI
808-521-7129

Original Message:
Sent: 06-29-2021 10:39
From: Peter Grey
Subject: Dampp Chaser, extreme humidity changes?

Nate,

In my opinion (based on experience) the best thing you can donis tell this client to get a different tech...one "better" than me...if you know what I mean.

Pwg

------------------------------
Peter Grey
Stratham NH
603-686-2395
pianodoctor57@gmail.com

Original Message:
Sent: 06-25-2021 10:40
From: Nate Reyburn
Subject: Dampp Chaser, extreme humidity changes?

Hi All,

I have a customer with multiple pianos in a commercial building where we see humidity changes from the 5% range to the high 60% range. The last tuning was done in the dry range, and they're asking me to do a warranty tuning because (SURPRISE!!!) the piano went out of tune. They're also asking me to install a Dampp Chaser. I've already spun my wheels with them as hard as I politely can towards some humidity control in the room.

My question is:
Would a Dampp Chaser do more harm than good? If you've got a 10mm spruce sheet like the soundboard with a 45% humidity on one side and 5% on the other, doesn't that cause some problems? I've installed lots of Dampp Chasers and it's a GREAT product, but I'm interested to hear whether you guys think it's appropriate in this situation.

------------------------------
http://www.facebook.com/ReyburnPianoTech
http://www.reyburntools.com
------------------------------