In a message dated 30/12/01 1:19:28 AM, fordpiano@lycos.com writes: << It would be so light and flexible that it couldn't absorb any energy. The opposite of the conventional thinking which is make it massive and stiff so it won't absorb energy. Well, how about make it so light and so flexible that it can't absorb energy? Phil F >> Phil; A few comments here if ya don mind......... << "It would be so light and flexible that it couldn't absorb any energy.">> Kinda the wrong slant here vis a vis soundboards??................A light and flexible rim may not "absorb any energy" but it certainly will 'dissipate' energy and be unable to reflect any, or at least very little, energy back to the board. The term mass has two quotients one being the physical size of a member and the other being the weight/density of the member...see Del's many comments vis a vis "select hardwood rims vs 'real' hardwood, i.e. maple/oak/etc., rims. Mass, in the molecular sense, without stiffness has no special benefit when applied to the materials we use in pianos. Some materials have more mass and less stiffness. An example of mass without stiffness would be a lead bar vs a like sized steel bar...the lead bar would be of more mass but would not have nearly the same stiffness as the lesser mass of the steel bar. Theoretically then a rim made of steel 'should' make a better performing mechanism, for sounboard purposes, than would a rim made of lead. It is possible for a small member to have more "mass", and stiffness, than a larger member...now as to whether a smaller, but greater mass, member is better for rims than is a larger member with less mass I will leave to the more cognizant. Just my thoughts. Jim Bryant (FL)
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