Sound waves(The behavior of soundboards)

[Richard Brekne]

Don Rose wrote:

> Hi Richard,
>
> Are you suggesting that the energy does not tranduce through the bridge to
> the soundboard, or that the bridge is initially an immoveable object?

Of course not Don. Where on earth in the words I wrote could you pull that one
out ? Of course there is an energy transfer going on... the question is what
the mechanisms for that transfer are.  I do not pretend to have the answer and
I find both positions interesting. Nowhere in my comments to Rons did I
suggest anything else then that his example about pressing down the string was
hardly a qualified proof that JD's and Robins position on this issue was
faulty.

> Energy is always conserved unless Mr. Einstein was wrong.

Yes, well Mr Einstein was quite capable of describing a whole lot of other
things beyond the grasp of most of us as well. I think it best to leave him
out of this as this particular entrance is waaayyyyy out of context.  Once
again, the discussion is about the mechanism of energy transfer... not its
existance.

> Time for someone to borrow a strobe light and set it to 440 hertz and have
> a good look at the bridge while playing A4. This *should* be doeable.

That would be interesting.

Ron N made a statement with some numbers attached about how much air was
displaced by some input to the bridge.... It made me wonder just how much air
displacement in the form of a compression wave in the appropriate frequency
range is needed to be audible.  Anybody know ? Sound intensity is normally
expressed in terms of watts / m^2, which is a bit of a different thing. It
doesnt take much for sound to become audible either, but how this equates to
how much actual air displacement takes place I havent been able to hunt down /
figure out yet.


>
> Regards,
> Don Rose, B.Mus., A.M.U.S., A.MUS., R.M.T., R.P.T.
>

Be of good Cheer !

--
Richard Brekne
RPT, N.P.T.F.
Bergen, Norway
mailto:rbrekne@broadpark.no