false beats from ?? -...

[Andrew and Rebeca Anderson]

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
>
>
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