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
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