Thanks, Fred. Admirable attempt to put a difficult concept into words. Five Lectures has its uses, eh? P In a message dated 2/10/2010 7:34:08 P.M. Central Standard Time, fssturm at unm.edu writes: On Feb 10, 2010, at 1:57 PM, _paulrevenkojones at aol.com_ (mailto:paulrevenkojones at aol.com) wrote: My question has more to do with actual cause and actual effect and the relationship of the two. I don't believe you're imagining anything any more than I know that I'm not when I experience the same thing. Our attempts to describe what actually happens to the string and the termination as cause/effect are on-going? We can certainly say that the string has a different shape, and that we experience a tonal difference, but is it simply a string condition difference? That's my question. My take is that it has to do with the distortion of the string being reflected back "at the bridge pin." The standard model of what happens when a hammer strikes a string is that a distortion is propagated along the string toward the bridge, then reflected back (actually two distortions, one of which goes back to the capo or whatever, but let's keep it simpler). Let's suppose the string was just pulled through the bridge with no massaging, and that a curvature extends in front of the bridge pin. The distortion of the string arrives, and there is, shall we say, ambiguity about where the string ends and the bridge (or pin or bridge plus pin) begins. The reflection backwards is diffused, parts happening sooner, parts later. Also, the impulse hitting the pin is diffused, less periodic than desired (especially after a few back and forth reflections). Adding the bend gives more geometric definition to the termination, hence a more precise and periodic impulse hitting the bridge/pin. Of course, it is never simple, and the closer you hone in, the less simple it becomes. The string's impulse/distortion never actually reflects at the tangent of the pin. It reflects behind it (the string, from a functional point of view, extends from somewhere toward the back side of the bridge pin to somewhere beyond the capo or agraffe tangent point). So we shouldn't think we are really making something _precise_ when we make a positive bend. We simply make it somewhat more precise. We also perhaps reduce the degree to which the vibration travels beyond the front and back _terminations_ by making the wire stiffer at that point (the work hardening caused by bending). Anyway, this seems to me to kind of explain the way in which the pitch and tone color becomes more focused following making those bends. That's how I picture it to myself, and I haven't yet heard something to make me believe differently. But maybe someone else has a different take. BTW, I wonder if making positive bends on both sides of the bridge might reduce the tendency of string to pass back and forth over the bridge. Perhaps a little. Regards, Fred Sturm University of New Mexico _fssturm at unm.edu_ (mailto:fssturm at unm.edu) = -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut.php/attachments/20100210/07c46025/attachment-0001.htm>
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