Soundboard stiffening-thanks Ron-N ( Here's that response I promised. )

[Ron Nossaman]

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>Dear Mr.Nossaman,
>      I thank you for attempting to empirically
>demonstrate the effect of downbearing, on a "mock-up"
>of a soundboard panel and rib. And I thank you for
>your very polite description, which has added to my
>understanding of the forces involved.
>      Still, I remain skeptical of your explanation.
>      You claim to have seen the board ends come INWARD
>as pressure is applied to the crown's apex---- and I
>would never call an eyewitness a liar!

Yet you in effect are, and have - twice.


>  But I am sure
>that you realize this contradicts common perception
>and observation, to say nothing of the laws of
>physics.

I realize no such thing. Gordon, have you actually tried it, or are you 
speaking for common perception, observation, and the laws of physics from a 
position of pure speculation?


>Unless something else is at work here!

What is at work here is what Phil Ford and I discussed, that soundboard 
crown is not an arch in the first place in spite of someone's intuitive 
impression that it must be so. Refer to our discussion for the details.


>      The only (legal) way to end this debate may be to
>put a very large micrometer across a piano rim and
>load the board, watching for expansion. ( Or
>contraction, as your prior assertions would seem to
>indicate.)
>      Your response will be most sincerely appreciated.
>
>      Thank You!
>      Thump

Build the rib and panel model, do the test, and pay attention.

Ron N

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