Overs Pianos wrote: > > At 8:29 PM +0100 24/1/05, Richard Brekne wrote: > >> >> . . . that compression damage is not really (necessarilly) damage per >> se at all, that a CC board that has lived a very successfully life >> and slowly but very evenly been compressed flat will retain (exactly >> because of said compression) a substantial part of its initial >> stiffness, explaining why so many old boards seem to perform so >> acceptably well . . . > > > I totally disagree that an evenly compressed board will have retained > its stiffness. If the cellular compression has gone out of a panel > enough to allow it to lose crown, it will also have lost a significant > degree of stiffness at the same time. In CC boards, panel compression > adds to the stiffness of the whole. If you're looking for a floppy > non-stiff panel that has front-end-punch with less sustain, the sunken > CC item will do it. There are numerous S-bent killer octaves out there > to prove this point (which were overloaded because they were > under-engineered in the first place). There may be instruments which > sound acceptable, which have what some would describe as an ordinary > board. But I have no doubt that these instruments would have a longer > tone (which, in my opinion, I happen to subjectively like) if the > board had retained that higher level of stiffness, which might have > been built into it at the time of construction. I am aware that you, and some particular others on the list disagree...and before going on let me just say I am certainly not any authority on the matter and can not confirm or not whether you and fellow minded are correct on this issue, or whether the opposing camp is. But I can observe that there are two (at least) schools of thought on the matter and the neither has seemed to come up with any unrefutable conclusive argumentation on this matter down through the years. I can also observe pianos out there... ones that have flattened out boards that are not caved in so that some areas of localized reverse crown exist... but simply pressed slowly and evenly down through the years. I find no lack of sustain in these, no lack of volume or power, no killer octave type of sound anywhere. On the subjective side I'd have to add that I find nothing that I personally would term as <<tonal negatives>> at all. The difference I do observe is a mellowed more rounded sound then I find in new pianos. What I'd like to see, tho perhaps may never... is someone actually measuring stiffness levels in various boards of various age and condition. Thats concrete enough.. quantifiable.. and can be easily put into a larger puzzle of other quantifiables to bring better into focus just what it is that some people seem to like so well about older boards... and some seem not to. None of this is meant in any way as a lack of respect for anyones knowledge, experience, whathave you... quite the opposite really.... > > On several occasions I've had technicians claim that "provided there > was an initial angle of downbearing set into an instrument, there will > still be a down bearing force on the board even after significant > soundboard drop has occurred". It isn't so. No down bearing angle > results in no loading on the board. Similarly, if a CC board has lost > its crown, it will have lost significant stiffness. Sunken boards > might sound OK if there is a working balance between > mass/stiffness/sound board area remaining. I will buy that it must have lost significant stiffness, but it also seems sensable that it has retained significant stiffness. Also as the crown decreases and thereby the upward pressure against the strings decrease... so does the downward pressure of the strings decrease. So as long as a kind of equilibrium is maintained I would imagine that tho the sound may indeed be changed somewhat.. this need not be seen as anything particularilly negative by many. Tho, I am the amature here... and my reasonings are based on ponderings of the many arguements on both sides of this fence I've tried to sift through down through the years. > > I strongly suspect that there is some sort of important relationship > between mass/stiffness/soundboard area which fundamentally influences > the tonal qualities of an instrument. Please don't ask me to elaborate > on this matter at this time. This theory remains just that, at present. Dont need to elaborate to be in agreement here. Whether or not any particular configuration results in influences that cause agreeable or disagreable acoustic charachteristics is another matter tho. > > Ron O. > Cheers RicB
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