More CC vs RC questions was RE: Killer Octave & Pitch Raise

[Richard Brekne]

Oh it holds up,,, as far as the reasoning goes. But stiffness, as you know, 
and for that matter spring rate is not all one is concerned with. You have 
the mass side of the equation to figure in.... at the very least.  You can 
easily achieve similar stiffness levels I would assume... with two different 
assemblies ( a CC and an RC&S) at least for a given RH, but achieving that 
and at the same time the same stiffness to mass relationships is another matter.

So varying panel thickness to achieve similar stiffness would probably 
insure dissimilar mass.

Cheers
RicB



Terry writes:

Maybe one thing being overlooked here is that, while panel stiffness is
increased by applying downbearing, the panel has a significant amount of
stiffness even with no compression at all. Even before it's ribbed, the
panel has stiffness. I don't know how the numbers would actually work out in
a working soundboard, but perhaps its not inconceivable that a CC board
could end up with similar stiffness as a RC&S board - by varying panel
thickness or whatever - maybe it's just that stiffness is achieved in part
by different means (and that may only be a small percentage of total
stiffness).

If what I am suggesting holds any water at all, it may be then that the two
systems might not necessarily produce greatly divergent tonal qualities.

Terry Farrell