Ric's point about substituting a looser pin raises the question: Does stringing grooves on a too soft bridge pin result in "false-beating"? Andrew Anderson At 05:32 PM 12/18/2005, you wrote: >Robert Scott writes: > >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 with the observations of performing the screwdriver test >for loose pins. > >----------- > >Except for the fact that you can insert a loose pin into a false >beating strings pin hole and the false beating can dissapear. Or >except for the fact that you can tighten the same false beating >strings pin and not get an improvement. Then too is the fact that >if sideways pin motion was the case one would not notice the false >beat until after that intial phase of string vibration. But that is >not the case. Further... given the amount of side bearing on the >pin, and given that the pulse that hits the bridge will always put >more pressure on that pin, I have to wonder about the speaking >length being changed idea. Further... one can observe when the >bridge pin is not in the same place as the notch that the string >also has a thusly undefined termination without any consistent >occurance of falsness. > >There are other problems with this concept as well. If there was a >conextion between pin loosness / sideways motion / and false beats >then one would expect there to be a correlation between the speed of >the false beat and the degree of looseness. Clearly there is none. > >I dunno... just doesnt add up to me really this loose pin thingy. I >think there must be another mechanism at work here. JMHO > >Cheers >RicB > > >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives
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