<table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top" style="font: inherit;"><div>Hey! Those are fun! (Thanks.) But the "music" behind "The Coupled Oscillator" is some of the utterly most unbearably hideous stuff I&#39;ve ever heard! (Definitely worth the price of admission, though, if you&#39;re a masochist.)<br /><br />Thumpe<br /><br />P.S. "Seems to me" that the bridge on a piano works as a crank: as the string oscillates, its effective length shortens and grows, and the elasticity within it yanks and releases the bridge top laterally, with that motion being transferred to the board in a "bell-crank", pumping motion contributing to "board collapse" and "bridge roll" on the speaking-length side. But restricted somewhat by the "waste" end of the string which would tend to transmiute* some of this "cranking" into a true up-and-down wagging of the bridge, and "funnel" some into a "shock-wave" through the material via its rsistance to
 stretching. But if the fundamental tone is thus sent to the board via this "cranking", what of the partials? Would perhaps the oscillations required by the bridge cranking in the fundamental vibration preclude the smaller ones from being effective (cancel them out) UNLESS transmitted via the "shock-wave" medium??? (And, no, I am NOT maliciously trying to explode your head! Honest!!!)<br />P.P.S Thank you, in your last post on this thread, for saying that the PRIMARY mode of transmission is gross<br />(physically, externally measurable) movement of the board by the string. Had I known that that was your contention (not that it was the SOLE mode, as I thought) we might have avpoided much tiff. (And a great, big, Kum-Bay-Yah to you too!)<br /><br />*A wonderfully useful new hybrid word that, no kidding, just "happened" as I typed "by chance"!</div></td></tr></table>            <div id="_origMsg_">
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                                <span style="font-weight:bold;">From:</span>
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                            Ron Nossaman &lt;rnossaman@cox.net&gt;;                            <br>
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                                <span style="font-weight:bold:">To:</span>
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                             &lt;pianotech@ptg.org&gt;;                                                                                                     <br>
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                                <span style="font-weight:bold:">Subject:</span>
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                            [pianotech] vibration stuff                            <br>
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                                <span style="font-weight:bold;">Sent:</span>
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                            Sat, Feb 2, 2013 7:26:02 PM                            <br>
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                                        <td valign="top" style="font:inherit;"><BR><BR>If anyone's interested in exploring some interesting vibration fundamentals, not piano specific though some of it usefully applies, Dr Dan Russell has been a good source for a long time.<BR><BR><BR><a href="http://www.acs.psu.edu/drussell/demos.html" target=_blank >http://www.acs.psu.edu/drussell/demos.html</a><BR><BR><a href="http://www.youtube.com/watch?v=_X72on6CSL0" target=_blank >http://www.youtube.com/watch?v=_X72on6CSL0</a><BR><BR><a href="http://www.youtube.com/user/drdanku" target=_blank >http://www.youtube.com/user/drdanku</a><BR><BR>Ron N<BR></td>
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