Inharmonicity - so what actually causes it ?question

pianoman pianoman@inlink.com
Fri, 14 Aug 1998 07:28:01 -0500


Hello,
Are you saying that if the bridge pins were not at an angle the string
would NOT vibrate in a cyclical pattern?
James Grebe
R.P.T. of the P.T.G.
 Since 1962 in St. Louis, MO
Home of Handsome Hardwood Caster Cups
pianoman@inlink.com        

----------
> From: Jim Coleman, Sr. <pianotoo@imap2.asu.edu>
> To: JIMRPT@aol.com
> Cc: nhunt@jagat.com; owner-pianotech@ptg.org; pianotech@ptg.org
> Subject: Re:  Re:  Re: Inharmonicity - so what actually  causes it ?
> Date: Friday, August 14, 1998 1:48 AM
> 
> Hi Jim B:
> 
> I is just a po desert rat, but when I was at the Conn Co. with Charles
> Walter and Dr. Kent, we did studies using calibrated strobe lights. We
> could see that the angled bridge pins caused the strings to vibrate in
> an elliptical pattern whose major axis oscillated from side to side by
> about 5 degrees.  You are probably visualizing the same thing. I don't
know
> for sure if that contributes to inharmonicity though. I do know that the
> lower partials of a note are more erratic in the Tenor area near the end
> of the bridge. I am guessing that it has something to do with the
insecurity
> of the soundboard in that area or perhaps the end of bridge effect.
> 
> Jim Coleman, Sr.
> 
> On Thu, 13 Aug 1998 JIMRPT@aol.com wrote:
> 
> > 
> > In a message dated 8/13/98 8:04:34 PM, pianotoo@imap2.asu.edu wrote:
> > 
> > <<As far as I know there is only a small effect on the inharmonicity
caused
> > by the terminations,>>
> > 
> > Thanks Dr. J;
> >  What I am visualizing is the different paths of vibrations reflecting
from
> > either end i.e., capo/agraffe end..mostly down & bridge/pin end....
mostly up
> > but also slightly down and sideways at the same time. Thereby changing
the
> > standing wave/partials differently at each end. Also the
soundboard/bridge
> > flexing much more than the agraffe/capo end.................
> > Hey, what do I know I's jus a po country boy :-)
> > Jim Bryant (FL)
> > 


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