---------------------- multipart/mixed attachment Del, 'Tis a pity that this experiment will have to wait until I am a=20 great deal more flush with cash. Surprising that the piano makers of the=20 world aren't running these experiments in an effort to perfect their own=20 designs. Greg Newell At 04:56 AM 5/8/2003, you wrote: >----- Original Message ----- >From: "Greg Newell" <gnewell@ameritech.net> >To: "Pianotech" <pianotech@ptg.org> >Sent: May 07, 2003 8:25 PM >Subject: Re: Oops... Re: Unusual rib structure? > > >Del, > Can this type of modal experiment be reproduced? and if so, how? > >Greg Newell > > >-------------------- >Sure. In fact it would be much easier today than it was then--computers are >much faster and the software is much more sophisticated. All you need is a >piano with a suitable soundboard set up so you have access to the >soundboard at specific intervals. As I recall we used a grid of >approximately 3" spread across the board. If you want the results to be >meaningful this means that the piano must be strung. Yes, you want to get >to all parts of the soundboard so that means drilling some holes through >the plate. You mount a suitable accelerometer on the bridge at some >suitable location. Using a Modal Hammer (i.e., a hammer of known mass and >with an accelerometer and a force transducer on its striking surface) you >tap the soundboard at each grid point with as much consistency as possible. >Once all the data from these hammer impacts has been recorded you process >the whole thing through some very expensive Modal Analysis software. For >your trouble you will get a picture of the soundboard panel vibrating in >slow motion at whatever frequency or frequencies you desire. Then, of >course, you have to interpret what you see. Interesting stuff. But pricey >and time consuming. > >Del > >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives Greg Newell Greg's piano Fort=E9 mailto:gnewell@ameritech.net=20 ---------------------- multipart/mixed attachment--
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