Been reading through all the posts again and again on this subject matter and one thing keeps coming through loud and clear. And this was echoed by the response I got when I put the matter simply stated to that online "ask a physicist" web site. Let me illustrate. Through the whole of it we ended up with both side allowing each other basically one concession. In both cases these were relegated to the status of insignificance. On the one hand it was recognized that the bridge does indeed get moved physically up and down to some degree by the strings and this to some degrees moves the soundboard. On the other hand it was also conceeded that completely immobilizing the bridge, inhibiting this physical movement, leaves some sound to be heard from the board. Seems to me like neither theory is adequate to fully explain the sound producing mechanisms in the system since neither seems to exclude the other. In fact one might say that neither could function at all without the other. Take for example the rock in the pond illustrated presented in this discussion to clarify this buisness about soundboard ripples. A rock is dropped into the pond and we see surface ripples. Brilliant... but what was completely overlooked was the fact that there are a lot of things going on under the surface at the same time. If these things did not exist... neither could the ripples, not just because obviously the cause of both would be missing, but because the two phenemena are co-dependant and support and reflect each other... they are actually the same thing really, its just that on the one hand the surface ripple is at the border between two medium, air and water....whereas the "rest" of the wave is traveling through the water and will do so until either its energy is dispersed completely and lost or it meets some other end point which either will absorbe it or reflect it back. In any case... it would seem to me that neither of the theories presented is sufficient alone to be the basis of any good working model of the panel. Tho either may have their uses as a particular perspective. just further pondering. -- Richard Brekne RPT, N.P.T.F. Bergen, Norway mailto:rbrekne@broadpark.no
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