Terry, and others who have commented. I THINK... and Vladan can correct me if I am wrong.. that the concept of <<coupling>> he is refering to is somewhat more along the lines of impedance matching then simple secure contact to the bridge. Cheers RicB Terry wrote: >I think having the strings snake through the offset bridge pins provides >much more positive attachment to the bridge than downbearing. In other >words, downbearing is a minor factor in attaching, or coupling, an >individual string to the bridge. That's what I think. No scientific research >on this topic on my part. But I'll betcha a donut I'm right! > >Terry Farrell > > > > >>Hello List, >> >>I have been reading the discussion about soundboard >>crown with great interest and feel compelled to add a >>possibly relevant observation. >> >>I am starting with the assumption that one intended >>benefit of the downbearing force is the increase in >>board stiffness. It's pretty obvious that the >>downbearing of a single string isn't significant to >>accomplish much change in stiffness. The increase in >>stiffness is the result of the composite force exerted >>by all the strings (however that force is >>distributed). >> >>There is however another design parameter that >>matters; that is the amount of downward pressure from >>a single string. This factor is important, because it >>determines the coupling of the individual resonator >>(string) to the bridge/board. This coupling parameter >>is a separate issue from board stiffness. >> >>So, we have the following problem: we have to adjust >>two parameters (board stiffness and string coupling), >>but we do it by adjusting one variable - downbearing >>force. What if the downbearing required to get the >>right board stiffness isn't the same downbearing that >>results in the best coupling from an individual string >>to the board? >> >>That, I believe, is a significant problem in the art >>of the soundboard design. One way to separate the two >>design parameters is to build a soundboard that either >>doesn't need downbearing in order to achieve the right >>stiffness, or perhaps a board that has an alternate >>means of adjusting the stiffness. Then, it would be >>possible to adjust the downbearing of each string just >>for the purpose of tweaking the coupling of the string >>to the board. >> >>Optimizing two parameters with one adjustment can be >>tough. >> >>What do you all think? >> >>Vladan >> >> >> >> >>__________________________________ >>Do you Yahoo!? >>Yahoo! Mail - Easier than ever with enhanced search. Learn more. >>http://info.mail.yahoo.com/mail_250 >>_______________________________________________ >>pianotech list info: https://www.moypiano.com/resources/#archives >> >> >> > > >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives > > >
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