Anyone who wants to can easily prove to themselves that the below simply doesn' t hold true. There are a variety of ways to go about punching gargantuan holes in this reasoning. One easy way is to take a simple center pin.... nice fat one say a size 24 and insert it under a unison on the bridge say 2-3 mm behind the front bridge pin. This gives you as floppy a bridge pin situation as could ever occur in real life and then some. Bring the unison up to tension and see how often you end up with a false beating string that was clean before. For that matter... pay attention to how often a string that started off being false gets clean by this experiement. Do this for say 10 different unisions to start getting an idea of the percentages involved here. It ends up that around 55 - 60 % of the time a <<loose pin>> and a false beat are coincident events. Hardly grounds for a cause and effect relationship declaration. But even if one stops up for a second and accepts for the moment this wobbly pin idea. It is then more likely that the pin is going to wobble in a for and aft orientation then sideways to begin with. For two reasons. One, the string is under considerable side bearing stress to begin with where as for and aft there is virtually no stress. Two.. the largest and most violent amplitude of vibrational motion by far is the pushing/pull of recursive pulses smashing into the bridge and their correspondant up and down motions. Beyond this and going back to a more involved perspective of the termination, the claim that the string makes no upwards and downwards motion beyond the bridge pin is an unsupported one. In fact, in the not so distant past there was a post describing a class given at a regional where high speed photography actually pictured this. Given a recessed notch which essentially provides no vertical support under the string at the proximity of the bridge pin... and the directional orientation of the string pulse... this isn't really all that difficult to imagine. The standard bridge / bridge pin configuration that defines the strings termination is a compound support. Cheers RicB One more time. There is no need for careful alignment other than keeping the notch edge out of the speaking length. The pin is the termination. The PIN is the termination. THE PIN IS THE TERMINATION. That is in both the vertical and horizontal excursion, just as the capo is the termination in both the vertical and horizontal excursion. If the pin is tight in the cap at the cap surface, where it won't flagpole, there won't be the classic false beat even with the notch clear behind the pin. The beat is NOT caused by the string sliding up and down the pin. Ron N
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