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Bacon felt

  • 1.  Bacon felt

    Registered Piano Technician
    Posted 09-14-2020 13:32
    For those proponents of the Ronsen Bacon felt hammers, what type of belly system (string tensions/rib scaling) are you matching to the hammers? Would you put them on a recent Steinway belly, say of the last 20-30 years’ production?


    Joe Wiencek


  • 2.  RE: Bacon felt

    Posted 09-14-2020 14:04
    Before the mystical "Matching the Impedance" guys reply, i'll offer some practical tips. 
    • You've picked the wrong hammers if you have to do a lot to them.
    • If the sustain has an immediate decay, the low shoulders are too hard
    • When testing the dynamic range from pp-ff, and ff is not available then the core area above the moulding is too soft.
    IMO, Ronsens are good when they are good, but require a lot of lacquer when they are not.  They are inconsistent because of their handmade nature.
    -chris

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    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 3.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-15-2020 12:24

    For those non-mystical "impedance guys" let it be known that there is a slight misnomer about impedance matching regarding piano mechanical properties. This misnomer may lead to a misunderstanding of how the belly/string/hammer properties function. For example, the soundboard impedance must be higher (not matched) than the hammer that excites it. If the soundboard and hammer were an exact impedance match, you would experience a sound akin to a thud. We hear this in old soundboards whose internal tension (a flat board) is next to zero. Understanding physics is the key to making improvements to the piano as we know it. There are technicians who understand physics and apply their knowledge to our discipline. I know of a couple technicians in the Northwest who contribute to the improved development of the piano. You usually see these technicians teaching at our regional and national conferences.



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    Roger Gable
    Gable Piano
    Everett WA
    425-252-5000
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  • 4.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-15-2020 13:05
    Impedance matching doesn't mean the goal is equality, it simply means they are matched, that there's consideration of the amount of energy delivered versus what the system requires or can handle.  To some degree that's what the voicing process is.  Because of different levels of resistance to energy transfer (that's what impedance is) you have to manipulate the hammer to absorb more or less energy.  Of course voicing involves other considerations as well, timbre, balance, evenness, etc.  I don't see it as a misnomer at all.

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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 5.  RE: Bacon felt

    Posted 09-15-2020 13:28
    Joe,
    My point regarding impedance is it has zero value in determining which hammer to use on what piano. They say impedance, i say its just personal preference.
    After all, if Ronsens can go Yamahas (big heavy boards), then the whole impedance thing has a serious applicability flaw somewhere.
    -chris

    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 6.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-16-2020 01:24

    You can put anything on anything, that doesn't mean it will be well matched or that you will appreciate the outcome. Put a Renner grosse 5 concert grand hammer on a 100 year old Chickering quarter grand and you will have an example of poor matching. Similarly, try a 12 lb Ronsen Bacon Felt hammer on a Bosendorfer imperial and you will not be getting the most from that instrument.  Those are clear examples of poor matching.

    Many pianos fall in between those examples, such as your Yamaha example (which I think is a medium weight assembly).  In this middle range many hammers will work but, depending on your tonal goal some hammers may get you there with less manipulation. Those would be examples of better matching. You suggested If you have to go to great lengths to make a hammer work you chose the wrong hammer.  I would agree with that generally and would call that a case of poor impedance matching  

    Old Steinways are tricky because not only are they light to begin with but over time the impedance characteristics diminish, they lose stiffness due to loss of crown.  In other words, that old board will be more easily driven. Thus the replacement hammer in that situation, if your goal is to recreate as much as possible the original tonal character, would one that is probably softer and lighter than the original.  

    BTW, yes the hammer hits the string but it is the soundboard's reaction to that impact that determines the overall tonal response and is an indication of the impedance characteristics of the entire assembly.  We don't calculate impedance, btw, we hear it.  And yes tastes vary. That doesn't mean there's not a lot of bad taste out there.  



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 7.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-16-2020 11:54
    When designing a piano assembly, whether we like it or not or want to use it as a model or not, impedance is what we are chasing.  While we may use beam formulas, calculations of mass and stiffness, deflection models, etc., our ultimate measure of the success of our structure are the impedance characteristics of the assembly which we determine aurally.  When we have a sense of those characteristics we choose a hammer (or voice a set of hammers) that not only best suits the structure but also appeals to our own aesthetic sense of tone.  We do that intuitively in the field when we confront a piano whose tone we don't like.  The two are bound together.  We don't measure impedance (not even sure how you would do that in a piano soundboard), instead we work with known engineering formulas that work in parallel with impedance outcomes.  Complicating those parallel calculations is the fact that the impedance characteristics vary in different parts of the assembly.  Those impedance and personal aesthetic characteristics guide us in our basic choice of hammers but they aren't the end all.  Inevitably some manipulation of the set (voicing) will be required to fine tune and balance those two issues.  If we choose poorly we can, as Jim states, end up chasing something we can't really achieve with that choice.  There is and always will be a difference between a too hard and/or too heavy hammer that is voiced down (made to absorb more energy) and one that starts out softer and lighter to begin with and requires less intervention.  If you don't recognize those differences then it doesn't much matter what you pick, but they are there and it would be best to learn how to hear them.  It can save you a lot of headaches. 

        
                He chose poorly

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



  • 8.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-16-2020 17:11
    Thanks to everyone who supplied responses. The subject got bigger than I was asking, but I have really been engaged in the entire thread. My original question about Ronsen Bacon hammers was inspired by my experience sampling many different types of hammers alongside the Bacon felt. Though my taste does not run to the heat or hard-pressed hammers such as Renner or most Asian piano hammers, I have felt that the Bacon qualities were too far from my tonal goal in re-hammering either existing soundboards or new soundboards. The samples I have from Ray were from at least 6 years ago or so, so I wonder if anything has changed in the density of the Bacon felt in that time period? Though David L.’s comment of too bulky of a hammer may have played into the "not quite there” quality that led me to choose another hammer over the Bacon. I thought that Steinway hammers are made using the Bacon felt?

    Joe Wiencek




  • 9.  RE: Bacon felt

    Posted 09-16-2020 17:18
    Bacon felt can be a little inconsistent. Ray went to the factory and showed them how to fix their machine to even out the felt quality a while ago. Then there was amazing Bacon felt. Recently the felt has not been as excellent as it was a few years ago, and even seems a bit denser in the last sets I got. So it is a little variable. The variability is in the felt, and and not so much the manufacture of the hammer I think.

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



  • 10.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-15-2020 10:49

    As an "impedance matching mystic" (I gave up grandiose self importance when I was a teenager), softer hammers tend to match well with lighter weight systems. Steinways tend to be a lighter weight system so Bacon Felt hammers work well there no matter what the vintage. Generally the hammer must have enough stiffness and mass to drive the system adequately and so a hammer that works well out of the box on a Steinway M may not be adequate on a Steinway D without some manipulation. Those differences are impedance driven. On the other hand a hammer that is too stiff or too massive can overdrive a lighter system and will require manipulation in other direction. Do you end up in the same place no matter where you start?  Well, I don't think you do. Since belies vary in their response even with the same model there are generally going to be some voicing adjustments required even if it's just to provide balance through the scale  

    That being said, tonal tastes vary and so something that appeals to one customer may not appeal to another.  The Ronsen Bacon Felt hammer will be a bit darker out of the box and likely will require some modest stiffening at the top end. If you prefer a hammer with a lot of drive then you may have to stiffen the entire set or choose a stiffer hammer like Renner Blue or Abel Natural.  In general, Renner and Abel hammers will require a fair about of needling, Ronsen hammers won't  

    The variability in the Ronsen response that our resident expert on everything cites I don't think has to do with inconsistency in the pressing but rather differences in dimensions. I don't prefer a softer hammer that has too much bulk or mass as it can be too dark and require a lot of stiffening. I'm generally somewhat specific with Ray about hammer dimensions (profiles) and that will make a difference as to how the hammer will need to be treated. The original Steinway hammer, pre WW2, was a generally light weight and softer hammer and worked very well, IMO.  



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



  • 11.  RE: Bacon felt

    Posted 09-15-2020 13:16
    "For example, the soundboard impedance must be higher (not matched) than the hammer that excites it. If the soundboard and hammer were an exact impedance match, you would experience a sound akin to a thud. We hear this in old soundboards whose internal tension (a flat board) is next to zero". 

    Roger,
    So then, what hammers would be such an impedance mismatch that would cause an old "no tension" soundboard to sound good?
    -chris

    ------------------------------
    Chernobieff Piano Restorations
    "Where Tone is Key"
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Lenoir City, TN
    865-986-7720
    ------------------------------



  • 12.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-15-2020 23:09

    I thought piano hammers had to hit strings before being able to move the soundboard. 

    Lighter soundboards usually will transmit hammer knock noise quicker. Lighter hammers produce less knock noise as do softer ones.

    Heavier hammers in a piano with a heavier board makes more "Thwap" sound during hammer string contact time than a lighter board with the same weight hammer. The lighter board will make more of a "Twhock sound




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    Edward McMorrow
    Edmonds WA
    425-299-3431
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  • 13.  RE: Bacon felt

    Posted 09-16-2020 09:21
    I reference hammer choice now based on tonal preference.  A Bacon hammer can make a U1 sound much sweeter, still with plenty of home sized power. Even though the Yamaha board may be designed to be bright, the hammer choice is an aesthetic choice. U1's function with Yamaha rocks and Renner blues could probably create a similar brash sound. I don't like that sound in a home, and frankly none of my clients appreciate that brash tone either. They both function, one over the other is an aesthetic choice.

    Choose a hammer designed to make a brash impact, and you will chase that brashness for the entire life of the hammer...it will always tend to harsh impacts, as impact control is the name of the game.

    Frankly re impedance matching reasoning, which I had subscribed to earlier, I am exiting that line of thought as I accumulate more and more data in my rebuilds. Harder heavier hammers simply do not create a sound I want my pianos to make, for any venue. Though most of my venues are home venues, even in certain performance venues, re harder hammers, (not heavier, as I do not install heavy hammers), I and the site tech wish we had stuck with the Bacon's we originally intended to use. We jumped ship and went to the Weikerts in the heat of battle having been scared away from Bacon's because of the impedance/venue argument which predominates. We are constantly chasing the treble tone with these Weikerts...the board is new with plenty of stiffness. 

    I simply want the sound the softer hammer provides. My thinking is more along these lines;  a softer hammer already possesses the organic resilience distributed throughout the entire hammer that I am looking for. Very slight stiffening of the hammer in select locations gets me the "pop".  Harder hammers just can not be brought down in the organic, well distributed fashion that a soft hammer already, by design contains.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 14.  RE: Bacon felt

    Member
    Posted 09-17-2020 10:49
    Doesn't a softer hammer have less of a life span? 
    How do you deal with voicing when string grooves develop so quick? Filing just reveals the harder denser core. I would think a heavy handed church pianist will destroy a new set of soft hammers in a short time and they ain't cheap.

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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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  • 15.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-17-2020 12:01
    A heavy handed pianist will destroy ANY hammers, along with a lot of other stuff. Pianos are not designed to stand up to abuse.

    A car driven hard 60,000 miles a year is going to need much more, quicker, than gas in the tank and oil in the crankcase than one driven nicely 12,000 to 15,000 miles a year. 

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 16.  RE: Bacon felt

    Posted 09-17-2020 15:16
    You've got that backwards. Softer lighter hammers do not wear as aggressively as hard heavy hammers. String impact cuts hard felt. String impact bounces off of soft felt.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 17.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-17-2020 16:09
    What Jim describes has been my experience as well.

    Alan

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    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
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  • 18.  RE: Bacon felt

    Registered Piano Technician
    Posted 09-22-2020 08:30
    What about other soft hammers? I'm thinking mainly of Steinway's current hammers. I tried them last year on a rebuild that has become my favorite.

    Does anyone have experience with Isaacs?
    I once tried some Pianotek Abels that were surprisingly soft, seemingly a different animal from Brooks Abels.

    Jim, do Ronsen Bacons just sound better to you?

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    John Pope
    University of Kentucky School of Music
    Lexington, KY
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  • 19.  RE: Bacon felt

    Posted 09-22-2020 08:59
    Yes....it's an aesthetic preference. Your aesthetic may or may not be different, but I really think its a aesthetic choice.  Having said that, my clients definitely agree with my aesthetic preference, but they may all be self selecting themselves for that aesthetic. They have, after all, self selected by choosing to hire me in the first place.


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