Leif Olsen wrote: > Hej list > > > We believe that a certain relatively small downbearing on every point on the > bridges is optimum, but agree on, that zero down-bearing at a string does > not mean zero tone there and negative (or uppbearing :-) ) means a tone too on > that place (phase-shifted??) why so? Im not sure I follow you here Leif, but I do know that Del has alluded a couple times to the question of whether crown is really needed. And the idea of negative bearing has been tossed around a couple times with bridge termination systems that would be compatible with that idea. > > > We intuitively know the difference between crashing an egg from the inside contra > the outside and the difference between an arched bridge contra a suspension > bridge... There has also been some argument about whether soundboard crown can be taken to resemble an arched bridge in any sense of the word...but your suspension bridge analogy is an interesting thought... :) > > My questions is this: > > Is there a qualified difference in "tonal responce" from a positive to a > negative crowned soundboard, which could be explained in terms of the forces > involved? I dont think anyone has done any studies on the matter if thats what you are asking. And very few of us have taken the time to really dink around with negative crown examples we have run into. They usually have so many other problems we just start fixin them or decide they are not worth it. Perhaps some of the more engineer minded can task themselves to an attempt at a mechanics explanation. > Given the bridgepins stays in there holes and the strings don't creep up the > pins, there seems to be symmetry in the forces if we give the "negative crown > board" a "negative downbearing"? Hmm... perhaps... at least I think I see where you are coming from... would you like to expound a bit on your thoughts here ? > > Regards > -- > Pianoshop Leif Olsen > > Member Of D.P.I.F. Denmark > > http://www.image.dk/~leifo -- Richard Brekne RPT, N.P.T.F. Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html
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