Hi RIc, This was a controlled experiment with solid terminations. So Jim Ellis has taken termination (and any soundboard or bridge influences) out of the picture, and has been able to produce, consistently, a "false" beating string based only on a single parameter: a rotation away from vertical and horizontal of the residual curl of the wire. That's how I interpret his article. Now in real life, there may be multiple contributing factors, but from the description of the experiment, it seems that Jim has effectively isolated a single cause. As to exactly how that translates to field experience, that is another question. Regards, Fred Sturm University of New Mexico fssturm at unm.edu On Aug 11, 2008, at 3:34 PM, Richard Brekne wrote: > I would like to know more closely just what kind of false beat this > exact <<cause>> is referring to. In particular whether or not this > false beat responds to a change in posture / mass of the compound > bridge termination most commonly found in pianos. > > Strikes me as important to re-read his opening statements as to the > basics of what false beats actually are. If, and I think he is, he > is referring to the classic false beat that we talk about so > often... then we are quickly in a range of contributing factors and > not into distinct causes per sé. > Let me illustrate. > If a false beat ala the kind Jim describes is also (simultaneously) > the kind that responds to a screwdriver being pressed onto the > bridge pin then clearly there are at least two factors involved in > this particular type of instance. One... the false beat occurs when > the curl is at a particular orientation to the string plane AND the > false beat occurs given a given massyness condition at the bridge > termination (which can be affected by addition/subtraction as > demonstrated by the screwdriver). > > This condition, if occurant then clearly shows that the classic > false beat is not caused by any one thing at all, but by a given > combination of events that allows the basic condition of the false > beat as defined to occur. > > If this eventually can be shown to be true... then it may be > possible (tho I do not say that it actually is) to identify some > exclusionary condition which preempts the false beat condition from > occurring at all. In other words.. by looking at the requirements > for the phenomenon, one may be able to find a way of ruling out them > being filled in the first place. > > It should be remembered that Jims experimental environment could not > account for the influence of the bridge itself, the soundboard, and > the interaction of the two in the end vibration that is transmitted > out into the air. It is entirely possible then that a string that > is beating such that two errant but close frequencies is present, > but the expected resultant false beat is canceled by some mechanism > laying between the string and its apparent termination, and the end > sound we hear. > > Cheers > RicB
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