M&A A

RicB ricb at pianostemmer.no
Sun Feb 18 08:27:38 MST 2007


Hi Mike

I've done that test so many times now its redougulous :)... which is why 
I have become more then a little skeptical about loose pins being a 
cause of false beats.  Find another one of those pins that responds as 
you mention... then push a little harder. The false beat will re-occur.  
How does that fit into the loose pin thing ?... If sideways pressure is 
supposed to compensate for the looseness of the pin.. then pushing even 
harder then it takes to quite the false beat should not have that affect.

A lot of the confusion seems to circle around what the word  "cause" 
actually means.  Loose pins may be a "factor" in the overall cause of 
false beat occurance.  But they simply can not be a cause in themselves 
because it quite obviously takes more then just a loose pin for a false 
beat to occur.  Otherwise false beats would occur without exception when 
a loose pin was present... and they very clearly do not.

The cause of false beating probably is more along the lines of an 
overall condition of to much springyness in the entire termination.  But 
it can demonstrably also be internal to the string itself... and the 
same screw driver trick will work.

The whole point is that if the termination oscillates in phase with one 
plane of vibration for a given frequency and does not for another plane 
of that same frequency, then a false beat will occur dependent on the 
strength  and degree of that in phase oscillation. This kind of thing 
can occur when the energy of the string is greater then the terminations 
ability to resist moving with it... in one or more planes at one or more 
frequencies.

I think its important to get closer to the root of the problem then 
simply buying into the loose pin thingy.... because we might actually 
solve the whole darn problem if we figure out whats really happening.

Cheers
RicB


    Ric and Paul,

    I, too, was a sceptic, having done the "sideways screwdriver pressure"
    test on the bridge pins of many false beating strings with no
    predictable effect on the beats.  But then I had one do exactly as the
    "myth" predicted:  The beats stopped entirely with very light sidways
    pressure (towards the string).  A little CA at the base of the pins and
    all the beating cleared up.   Here's what I conclude:  Loose bridge
    pins
    can be the cause of SOME false beating, but is not the cause of ALL
    false beating.  For those who have never experienced it, it will remain
    a myth.  For me, it is now one of SEVERAL POSSIBLE CAUSES to be
    included
    in the troubleshooter's bag of tricks.

    Mike



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