Ron Nossaman wrote: > >I have > >not heard that restringing programs take any of this into consideration > (perhaps > >it is not possible yet or perhaps it is not needed ??). > > * Well, the short version is this........ > > I believe that computation of the impedance balances between the strings and > soundboard are, indeed, possible. I further believe that it is imperative > that the designer and/or rebuilder consider the performance potential of the > soundboard, both from a design, and condition standpoint before the strings > are installed. In other words, I think it's both possible and needed... and > that's the short version! A couple questions here... I know several guys who routinely use a scaleing program to redesign the scale when restringing / rebuilding. These fellows typically are repairing cracks in the soundboard (shimming). They take care to check "downbearing" before and after lessening tension on the strings. Often they lower the plate a bit (something I question the reasoning for ... read Ed McMorrows book). No one over here in Norway seems to fool around with moving bridges, tampering with bridges, or other such things. So when redesigning string scales it seems possible to me that they are playing bingo to some degree. Without knowing more about the condition of the soundboard then its present downbearing / string deflection readings, how can one be sure that any given new string scale and or lowering the plate will be benificial ? The results seem to bear out my skeptism in this regard. Often as not the results are less then satisfactory soundwise. Your thoughts ??.. Also you mention some info Del has at one time offered about viewing ribbing as a center beam. Can you refer me to any specific reading on this and other such soundboard related material ? When I am restringing after a soundboard fix, I routinely use the same scale, and try to achieve the same, or slightly less downbearing. I do this simply because I do not feel confident in changing things without knowing more then I do about these issues. As far as lessening downbearing (gut feeling really), seems like an old soundboard must be weaker, ergo less stiff / resiliant. Doing this combined with very slow and even tension raising to bring the piano up to pitch (typically one month) seems to be my best guarantee of not wrecking the sound of a piano. As far as this buisness of hammer angles.... Seems to me that the importance of this is slightly overstated with regard to phasing. Tho I must admit I have not methodically experimented with this, and on the surface of it the arguments for hammer angles corresponding to string angle are sensible enough. Most grands today are such that one can file hammers to match the string angle as the difference between the two is not all that great. Still it seems to me that most problems with "phasing sounds" or other such sound deficiencies are probably rooted elsewhere. If the hammer hits all strings in a given unison exactly at the same time, and it sounds bad still, I look elsewhere for the problem. Richard Brekne I.C.P.T.G. N.P.T.F.
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