Hi Richard, Without a very logic explanation myself at this moment, the backchecks height change the synchronism hammer check/key bottom. All this act at the same moment the tone begin to be produced, so it seem "normal" that an influence exist. But I am yet to find a good explanation ! Checking height, also, gives more or less strength on the repeated notes, may be only because lower checking oblige the pianist to play with more force/articulation. That is funny as any setup that oblige you to play stronger gives also an impression that the tone is stronger , for instance the infamous repetition springs added on the jacks on vertical pianos, that slow the finger and oblige you to produce a strong attack. Best Regards and a good week . Isaac P.S I like when I ask very special questions to someone and he answer "' yes of course" almost like if it is a stupid question. I had the same to some techs about if the install the Steinway iron plate under tension, and they look at me like if I was crazy to ask ! -----Message d'origine----- De : pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]De la part de Richard Brekne Envoyé : dimanche 15 août 2004 22:27 À : ilvey@sbcglobal.net; Pianotech Objet : Re: punching, it hits you David Ilvedson wrote: >I have heard of washing and drying punchings to change density and mainly stability... > >David I. > > > > Well, I have to admit that a few years back (4-5) this concept was new to me as well. Andre started talking about it, and then we who know him here of course started giving it a try. First for me was simply noticing the difference between pianos, and trying to experiment a bit with trying out different things. I remember a Petrof grand that I ordered some very hard punchings for through the Steinway rep here. (course I told him is was for a Steinway :) ) I was really suprised at the difference, but then Petrofs are (were) known for very soft action felts almost as if they wanted a lot of give in the action. In anycase the difference was obvious, and everyone who plays on this agreed that the difference was for the better. And interestingly enough many students remarked that they thought the tone of the instrument had improved. This brings me to another one of Andre's suggestions... that about the height of the backcheck having an impact on tone. Now this one is just plain weird sounding... I'll be the first to admit it... but there it was. When Andre was up here a couple years back he demonstrated it to 5 of us, and no one could avoid admiting that he'd changed the tone... the openess of the tone on the notes he'd adjusted. I asked the famous Japanese pianotechs Mr. Ono and Mr. Takahara about this too whilst I was in Japan this summer, and they both immediatly responded along the lines... "but of course-- didnt you know that ???"... tho to this day I have yet to find a satisfactory explaination for why the height of the backcheck can influence the openess of the tone of the piano. Anyways... I've come to learn, as Isaac has as well... that Andre' is full of a lot of piano tone knowledge. Much of it based on hands on experience as opposed to engineering expertise. Funny how that still in these days almost always yeilds the best advice. In anycase... like I said... I suggest you start experimenting around with punchings densities just to see for yourself. Another felt I've been thinking of trying to replace with some of this Wurzen stuff is the whippen cushion. I'll have to wait tho until the appropriate felt is available from Wurzen... and I have this Petrof in mind once again. Cheers RicB _______________________________________________ pianotech list info: https://www.moypiano.com/resources/#archives
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