On 2/3/2011 11:22 PM, Roger at Integra.net wrote: > Ron, > I would have a tendency to disagree with your analyst. First, if a false > beat was usually caused by a loose pin (which it frequently is) then > there isn't a rational reason why string seating cures a major portion > of false beats. Seating sometimes stops the beat because it jams the string against the bridge cap hard enough to stop the pin flagpoling - sometimes. >What seems more rational is that the seating process > beds the string against the pin and bridge to create a uniform > termination during the entire circular motion of the string -- remember, > strings rotate, not just move up and down. In the situation pictured, > the rotational movement of the string would indeed vary the termination > length and/or create an "energy leak, or skip" past the termination > sometime during the rotational cycle. That picture "screams" of an > situation where the energy can't be uniformly reflected back into the > string during the entire rotational cycle. Again, the pin is the termination in all directions of string termination unless the notch edge extends into the speaking length. The string doesn't slither up and down the pin except perhaps the first millisecond of the attack impulse, well before the beat can be heard. The friction between the string and pin doesn't allow it. The beat comes from the different "effective" speaking lengths caused by the more rigid termination in the vertical direction, and the springy termination in the horizontal. That's why the screwdriver test works. > Your mention of using a screwdriver to temporarily "stake" the pin for > testing is, in my opinion, suspect many times. When the false beat seems > to be reduced or disappear during this test, you will, with close > examination, find that you are not always hearing the effects of a more > solid pin, but only the result of a dampened bridge cap, giving you the > impression that the false beat has disappeared. Close examination? What method do you use to indicate a "dampened" bridge cap? And how do you get an impression that the beat disappeared if it didn't? If the screwdriver "damps" the cap, then you can push directly on the cap and get the same effect, or on the adjacent pin. This isn't the case. Have you actually tried it? The beat suppression is a direct and repeatable result of stopping the pin flagpoling, and it doesn't take much pressure to do it. >This is not to say that > the screwdriver test is an invalid test, but is to say that you may find > yourself barking up the wrong tree. No, I'm not. How about you inform us what, specifically, is a valid test that barks up the right tree? Ron N
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