This is a multi-part message in MIME format. ---------------------- multipart/mixed attachment > Hi, > Could we add to the list of causes of false beats the hight of the > bridge pin above the string? > A taller flag pole sways easier than a short one. While the pin height might very well affect the beat RATE, the flagpoling still has to be there in the first place for the typical loose pin false beat. > ??What is the relationship between the size of the wire and cause of > false beats?? There has to be a relationship. The effective increased speaking length of a given springy termination will be longer with a more flexible wire, shorter with stiffer, assuming the actual effective termination just past the bridge pin is the same in both cases. > It seems to me that 90% of false strings are from C6 up/ 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 ---------------------- multipart/mixed attachment A non-text attachment was scrubbed... Name: beats.jpg Type: image/jpeg Size: 151515 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/c9/80/1f/ab/beats.jpg ---------------------- multipart/mixed attachment--
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