Ric Brekne wrote: > ...In fact there is no mechanism for how this should work given > at all as far as I can see...Looks like more of magic past to me... Ric, it's not magic. When struck, the string starts out vibrating only in the up and down direction. But it quickly precesses into an elliptical path, as described by Peter Weinbreck's articles in the 1970’s, and perhaps even earlier. Since the string is vibrating both up-and-down and right-and-left, the termination point must be viewed separately in both axes. If the termination point is the same for all directions of vibration, then all is well, and every vibration is at the same pitch. But if the termination point for up-and-down motion is different than the termination point for right-and-left motion, then these two motions will occur at different pitches, hence the false beat between them. When a bridge pin is loose, it does not resist right-and-left motion as well as the bridge cap resists up-and-down motion. Therefore the right-and-left vibration effective speaking length is slightly longer than the up-and-down effective speaking length. This is consistent w! ith the observations of performing the screwdriver test for loose pins. Robert Scott Ypsilanti, Michigan
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