>At the risk of oversimplification, isn't a crowned soundboard just a big >spring, the more you compress it, the more rigid it becomes? > >David Love >davidlovepianos@earthlink.net > David, This is the point that I was trying to make. I believe that the soundboard is essentially just a big spring. A spring doesn't get more rigid or stiff the more you compress it. Within its working range it has a constant spring rate or stiffness. If a spring's spring rate is 100 lb/in. then it takes 100 lbs to deflect it the first inch. It takes 100 additional lbs to deflect it another inch. It doesn't matter if you start from a zero deflection point or an initial 1 inch deflection point - the spring rate (or stiffness) is still 100 lbs/in. It's not getting stiffer because you're putting load on it or deflecting it. True, it takes twice as much load to get twice as much deflection, but that is still a constant stiffness. I would expect a soundboard to work the same way. If the board is actually getting stiffer as a result of applied load then it's not acting like a spring or a beam, and I would like to understand what mechanism is causing that to happen. Phil Ford
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