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Nice work David.... I got to re-reading some of this stuff, and was
especially interested in what the three big time physists had to say on
the general question of how and in what manner the strings get the board
moving.
<p>I just had to re-include this earlier given quote from G.Weinreich...
<blockquote>Dear Mr. Brekne, in this case the simplest process -- transverse
motion of
<br>the soundboard -- is also the dominant one. Although it is possible
to
<br>resolve it into waves traveling through the soundboard, I think you
can
<br>understand it better as the bridge giving rise to standing waves in
the
<br>soundboard which are, in fact, what are called modes of vibration of
the
<br>soundboard.</blockquote>
<p><br>I note that he actually says here that visualizing... or understanding
soundboard vibration is one thing,,,, and not necessarily the same as a
more complex and complete mathematical or physics description.
<p>Another thing that continues to discomfort my meanderings on all this
is the constant weight placed on the soundboard modes of vibration. These
seem to govern the overall sound in a way somewhat more inclusive then
simple sympathetic resonances with string frequencies that are in coincedence
at any given time. I keep getting the feeling that there is some more general
and overall filtering effect constituted by these modes, and have trouble
resolving that thought with the notion that the soundboard simply vibrates
up and down in simple transverse motion identically reflective of the actual
string frequencies. That difficulty has lessened a bit since it seems apparent
that the soundboard does indeed vibrate in a manner somewhat more complex
then the simplest of models presented during the discussions, but still
it leaves much to be unresolved in this laymans mind of mine.
<p>I wholeheartedly aggree tho that the subject manner in all its tangents
is of great interest and of more value then maybe some of us give it credit
for.
<p>RicB
<p>David Skolnik wrote:
<blockquote TYPE=CITE>At 11:18 AM 02/27/2002 -0500, Stephen Birkett wrote:
<br>>Now that the discussion has calmed down - I found it difficult to
follow
<br>>the various
<br>>threads while the salvos were going back and forth - perhaps this
would be
<br>>a good point
<br>>to present a short, dispassionate synopsis of these key experimental
<br>>anomalies and
<br>>observations that need explanation.
<p>In the spirit of synoptic comradery, I would like to offer this, hopefully,
<br>inclusive chronological list of the various related threads of this
topic
<br>since its origin on November 30, 2001. This would presumably
be of use to
<br>anyone attempting to follow the discussion using the archives.
<p>Negative Bearing
(11/30/01 - 12/04/01)
<br>Sound in soundboards
(12/03/01 - 12/04/01)
<br>Soundboard grain angle (12/03/01 - 12/06/01)
<br>Modal Analysis
(12/04/01 - 12/06/01)
<br>Sound waves
(12/05/01 - 12/08/01)
<br>Soundboard vs string
(12/08/01 - 12/10/01)
<br>Sound waves(The behavior of soundboards)
(12/15/01 - 2/07/02)
<br>Rocking bridges (12/24/01
- 12/31/01)
<br>Sound Waves physics
(12/25/01 - 12/26/01)
<br>Sound Propagation
(1/06/02 - 1/10/02)
<br>Sound waves(a neat experiment) (1/17/02 - 1/20/02) Also: Sound
waves
<br>(another experiment)
<br>Wapin Bridge
(1/24/02 - 1/31/02)
<br>On the course of discussion (2/04/02 - 2/05/02)
<br>Bass Bridges made of Spruce! (2/25/02 - 2/27/02)
<br>Aprons and holey bridges
(2/27/02 - 3/01/02)
<br>Vibrating strings and bridges (3/14/02)
<br>On the course of discussion(the behavior of soundboards)
(2/25/02 -
<br>2/27/02)
<p>There is a pattern on this list, of significant discussions tapering
off,
<br>unresolved, some, perhaps, to reemerge at a later date. This
discussion
<br>was too important (and exciting) to be consigned to such a fate.
Perhaps
<br>too, it has outgrown the present format of the list. I don't
know if it's
<br>possible, and I certainly don't know if it is advisable, but, over
the
<br>years, the original list created spin off lists, ie, CAUT, PTG-L, HUMOR...
<br>. More thoughts to follow.
<p>David Skolnik</blockquote>
<br>
<br>
<p>--
<br>Richard Brekne
<br>RPT, N.P.T.F.
<br>Bergen, Norway
<br><A HREF="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A>
<br><A HREF="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broadpark.no/~rbrekne/ricmain.html</A>
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