Delwin D Fandrich wrote: > > > > Aslo... The fundemental frequency mode pictures I have seen never follow > > the edge pattern of the soundboard /rim. And it would be a bad thing > > indeed if the fundemental mode was so large. I dont believe that > > Steingrębers sand gathering proceedure has anything at all to do with > > the fundemental reasonant mode... Lot of good a cutoff bar is if the > > vibrational modes dont get affected (limited) by it ... or what ? > > Never, of course, is an awfully inclusive word. Unless, of course, you have > been privilaged view all of the photographs ever taken of these tests. But, > yes, there are fundamental modes this large. The common style of rib > feathering encourages this performance. > > Del > Certainly havnt seen em all, not by a long shot. But I have seen a good few of these through the past few years now. They do not reveal fundemental frequency modes like this at all. I still have to question whether or not Steingrębers proceedure has anything to do with Chladni patterns per se. Would be easy enough to find out tho. Just identify the fundemental and resonate the board at it to see where the sand ends up. I'm betting the mode will be quite a bit more oblong in shape, and quite a bit smaller. But if not, well it wouldnt be the first time I've been wrong. :) Cheers RicB -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html
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