Hi folks. If we are to accept that a false beat is tied to the supposed variance in speaking length that the below math and reasoning tries to justify, then we must (and I mean imperativly must) expect a beat rate that diminsishes with the strings ability to deflect the pin as the strings vibrational decay developes. But the false beat rate is _/constant/_. That in itself is enough to discount the hypothesis below. Further, the string already exerts considerable sidebearing pressure on the pin, and by the time the string starts oscillating in elliptical path it hasnt enough energy to overcome this side bearing one way or the other to begin with. Thirdly, the initial pulse is 100 % vertical. The slight angle of the pin will deflect a very small portion of this in a purely sideways motion... or to put it in otherwords, there is only a very small purely sideways componet of the force exerted upon the pin by this initial energy of the string. Tho the math (below) itself is sound enough, the precept the reasoning is based on doenst hold and the direct consequence of a diminishing false beat rate is at odds with the observed constant false beat rate that actually occurs. I just dont see how one can do anything else then reject the idea. Cheers RicB Ron N writes: Look at the math on just the speaking lengths, ignoring oscillation frequency of the pin and wire stiffness. Let's say the loose pin produces an effective speaking length difference of 0.001" between vertical and horizontal excursion of the string. U=unison number T=tension F=frequency D=wire diameter in 0.001" L=speaking length in inches Fork=A-4 pitch F=0.0625*fork*2^(1/12*(U-1)) T=((F*L*D)/20833)^2 so F=((T^0.5*20833)/L)/D Figure the frequencies of two speaking lengths 0.001" apart at the same tension, and you have a beat rate. Ron N
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