Hi all, I was reading through the five lectures again--been a while. In the coupled motions article the point is raised that the bridge is a springy termination which cause the string to "think" it is longer than it is lowering the frequency. Ric has asked often why a screw driver on a bridge pin may initially stop a false beat but when more pressure is added the beat may start up again. The simple answer may be that adding "apparent" mass by touching the screw driver makes the pin less able to spring--but as pressure is increased past a certain level, the frequency will begin to change--causing a return of the falseness. If this is the case then as Ric increases the pressure the beat should change it's speed (that is until the screw driver slips off and makes a hole through the soundboard *grin*). As a side issue it may also offer an explanation of why CA glue works. It may simply makes the bridge a bit denser--providing a more support--making the wood less springy. I.E. It hasn't got much to do with the bridge pin being looseit has to do with the wood failing to be dense enough. That nicely explains why a bridge pin can be so loose it can be removed with just your fingersand still not produce a false beat, or it can be so tight that a captive hammer is needed to remove itand still produce a pronounced beat. Here is the quote (out of context) from the article that got me thinking along this direction: "If the support is "springy," that is, one which displaces sideways in the direction in which the string applies a force to it, there will no longer be an exact node at the support. Instead, the extrapolated node will be somewhat beyond the physical end of the string; or, in other words, the string will "think" that it is longer than it really is, causing it to lower its frequency." Comments? Regards, Don Rose, B.Mus., A.M.U.S., A.MUS., R.P.T. Non calor sed umor est qui nobis incommodat mailto:pianotuna at yahoo.com http://us.geocities.com/drpt1948/ 3004 Grant Rd. REGINA, SK, S4S 5G7 306-539-0716 or 1-888-29t-uner
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