> If there are false beats, then the vertical component of the string vibration > would have to vary cyclically. > Bob Scott Only if you explain false beats as amplitude modulation. Frequency modulation makes more sense to me, as explained by Jim Coleman Sr. (difference in speaking lengths in vertical and horizontal modes causes pitch change. This can be due to unclean notch OR bridge pin which wobbles in horizontal mode, causing the string to act longer in that mode). Bob Davis
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