Inharmonicity - so what?

[Richard Moody]

Del Wrote
	> By driving the soundboard with a shaker



Can differences in the fundamental resonance be noted with the dampers up
or down? 

Also do you mean the fundamental of resonance freq. or the predomoninant
resonant freq? 

ric

----------
> From: Delwin D Fandrich <pianobuilders@olynet.com>
> To: pianotech@ptg.org
> Subject: Re: Inharmonicity - so what?
> Date: Thursday, August 20, 1998 1:23 PM
> 
> 
> 
> Richard Moody wrote:
> 
> > ----------
> > > From: Delwin D Fandrich <pianobuilders@olynet.com>
> > > To: pianotech@ptg.org
> > > Subject: Re: Inharmonicity - so what?
> > > Date: Wednesday, August 19, 1998 1:54 AM
> >
> > >If the fundamental resonant frequency of the string loaded
>soundboard
> > assembly
> >
> > How is this freq determined?
> > Ric
> 
> -------------------------
> 
> By driving the soundboard with a shaker.  A shaker is somewhat like a
> loudspeaker motor assembly except that they are usually fully enclosed
and they
> have no cone.  Shakers are designed to transfer specific amounts of
energy to
> some mechanical structure.  The shaker is excited by a variable
frequency sine
> wave generator along with a power amplifier.  The frequency generator is
swept
> through an appropriate frequency band and the resonances noted.  These
can be
> detected either by ear -- sometimes confusing -- or by an accelerometer.
 The
> accelerometer output is analyzed with some type of signal readout.  The
readout
> can be anything from an accurate ac voltmeter, an oscilloscope or an FFT
> analyzer.
> 
> -- ddf
>