On 5/11/2012 4:08 PM, Alan Eder wrote: > Got it, and thanks for the explanation. Is there any simple > demonstration model that can readily A/B the effects of crown (with its > attendant resonance/sustain and power/projection) vs. no crown, > preferably on the same piece of surrogate soundboard? That is what is > really needed to faithfully get the point across. That's what's needed to get the point across, agreed, but the problem is that the point is incorrect. Crown, per se, isn't necessary to soundboard function. Crown in a compression crowned board as is used by Steinway is an artifact of high panel compression bending flat ribs up into a curve when the panel rehydrates. The ribs are actually resisting the formation and maintenance of crown. Loading this panel with string bearing pushes the crown flatter, and makes the assembly stiffer as the panel compression level reaches it's physical limit. The stiffness is what you're after. Given enough stiffness built into the assembly, crown isn't needed. Stiffness can be achieved with crowned ribs, acting as support beams, but the ribs need to be considerably stiffer than those in a compression crowned board to support string bearing with measurable positive crown without high panel compression levels. I not only don't know of a simple demo of how soundboards work, I don't know how to explain it adequately without spending most of a day doing it. Ron N
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