Terry, Please tie a long rope to a wall, stretch it and pluck it. You can SEE the vibrations bounce off the wall, and head back your way !!! This might be audibly "moot" in piano construction, on a bridge 2" tall; but it is quite scientifically demonstrable that vibrations travel WITH the grain more rapidly than ACROSS it. ( There goes that "density " thing , again! Gosh! ) The fact that so many superb manufacturers used verically laminated bridge cores in the past may really just be a sign that they were dedicated to sqeezing out every drop of energetic efficiency they could, in what was once a very competitive market. ( And they didn't have the Internet to goof off on,in 1898, absorbing their "time energy"! ) Thump --- Terry <terry@farrellpiano.com> wrote: > Nawwwwwwwwwww. Your skipping rope is just like the > speaking length of a > piano string. You pluck it or whack it and it > vibrates. Period. It vibrates. > The length of time it vibrates will vary directly > with the > solidity/immobility of the speaking length > terminations (a cast iron capo > bar works better than a hunk of loose rubber). > Similar with the soundboard. > It vibrates. The more solid/immobile/massive the > rim, the less the > soundboard can vibrate the rim, and the less energy > is lost at the rim. I > really don't think there are things zipping back and > forth and bouncing off > this or that. I do know that it makes for great > graphics in four-color > brochures. That kind of thinking is consistent with > the thinking that bridge > wood/laminations need to have the grain oriented a > certain way so the sound > energy can pass through the bridge from the strings > to the soundboard. Don't > think so. > > Terry Farrell > > > > Hi Terry, > > > > Take a skipping rope. Tie it to a concrete wall or > some other massive > > object. Put a pound of tension on it. Now "pluck" > it. Does the wave > > dissipate when it strikes the wall or does it > "reflect" back from the > fixed > > end of the rope? I'm certain that it is part of > the reason that pianos > with > > massive rims generally exhibit good sustain. > > > > At 11:31 AM 19/02/2005 -0500, you wrote: > > > What do you base this on? Does anyone know the > > >origin of this kind of thinking? > > > Not even Steinway marketing would agree with > this: > > >Terry Farrell > > > > Regards, > > Don Rose, > > > _______________________________________________ > pianotech list info: > https://www.moypiano.com/resources/#archives > __________________________________ Do you Yahoo!? All your favorites on one personal page – Try My Yahoo! http://my.yahoo.com
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