---------------------- multipart/mixed attachment Del, Can this type of modal experiment be reproduced? and if so, how? Greg Newell At 06:25 PM 5/7/2003, you wrote: >----- Original Message ----- >From: "Sarah Fox" <sarah@gendernet.org> >To: "Pianotech" <pianotech@ptg.org> >Sent: May 07, 2003 2:02 PM >Subject: Re: Oops... Re: Unusual rib structure? > > > > Hi Del et al., > > > > So these rib ties were somewhat of a "missing link" between the old > > no-cutoff-bar design and the more modern cutoff bar construction??? = Just > > curious -- What was the evolutionary history, in a few sentences or= less? > > > > Thanks! > > > > Peace, > > Sarah > >(Sarah, you should by now know better than to ask me to whip something like >this off in "a few sentences or less....") > >Your Wissner, like almost every other U.S. built, and now Asian built, >concert grand traces it design origins back to the Steinway Model D. The >Model D, in turn, traces its origins back to a synthesis of various pianos >that formed the transition between the harpsichord/fortepiano and the >so-called "modern" piano. Steinway actually introduced very little that was >truly new and original. One of the things he brought forward was the large, >open soundboard. (Yes, I know that many pianoforte's did utilize some form >of soundboard cutoff. Most of those I've seen, however, were basically >floating cutoff's however. Much like the straps used by Steinway, et al.) > >By the 1880s piano makers were just beginning to investigate the >performance of various rib structures and soundboard shapes and >configurations. And by this time the Steinway pianos had already became >exceptionally powerful marketing and manufacturing successes. Market forces >then, as now, dictated that there were more followers than leaders in the >madness that made up the late 1800s and early 1900s piano business. Even >though many builders were building better, and better sounding, pianos than >anything coming out of the Steinway factory, they tended to get lost in the >marketing and promotional wars that could, and did, become quite brutal. > >Many piano makers seem to have had a reasonably good grasp of the basic >design principles that go into making a good, efficient soundboard >system--we still occasionally see their products in our shops yet today. >Well though out and often highly innovative work. But they didn't survive >the marketing wars any better then than they do today. > >Ironically, even though Steinway marketing today carries on about the large >soundboard/large amplifier foolishness, at one time somebody in the company >clearly understood the value of a good soundboard cutoff bar--witness the >shape of the soundboards in some of their early vertical piano designs. But >this never carried over to their grands. At least not in the later >production designs that have now become locked in tradition--some of their >earlier vertical piano designs did have relatively substantial cutoffs. > >Pianos with purely compression-crowned soundboards tend to lose their crown >and, hence, their ability to carry sustain, through the upper tenor and >lower treble sections relatively quickly. (Relative, that is, in terms of >piano life.) Both the addition of the so-called "resonator" strap (which >stiffens up the soundboard assembly in an area which really should be >infinitely stiff) and the upper bellyrail-to-rim strap are indications that >somewhere back there someone in their design department understood at least >the basics of why this was happening. These two devices both help, but do >not solve, the real problem. > >Back in the late 1980s I was working on a small soundboard design and was >able to look at the design I had come up with using a rather primitive >modal analysis model. It was fascinating to watch the bridge move up and >down while a mode in the forward bass corner simultaneously moved exactly >180=BA out of phase with it. Sound energy is simply transferred back and >forth and is effectively cancelled. A second study done with a soundboard >cutoff appropriately placed removed this area of the soundboard and >increased the efficiency of the whole system. > >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--
This PTG archive page provided courtesy of Moy Piano Service, LLC