Will Truitt wrote: > Might that not be a Good thing - > the tighter the radius, the stiffer it will be, and the less tight, the more > flexible; all else being equal. As has been the case many times, all else is not apparently equal in this case either, since the crown radius has nothing whatsoever to do with rib stiffness. Choice of radius just gives you some control of residual crown under load, after load deflection. >The greatest need for stiffness along the > rib would be under the bridge, where the strings are pressing down. And we > want the panel and ribs to be be more flexible out towards the rim - which > is why we thin them. I have long wondered if the responsiveness of the > soundboard system might be improved by designing a rib in a parabolic shape > to meet these dual needs. I don't know if it would be a meaningful > improvement, one that improves it but trivially so, or does nothing at all. > Nor do I know how we would assign real values to the shaping of such a rib. > > Food for thought, maybe it's junk food.... > > Will Truitt The feathering configuration can easily address this, whatever the crown profile (within reason). Ron N
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