Dear Ed: As you probably already know, the wild string effect is produced by a string vibrating at two frequencies at once. For example, when a string has in- dented the bridge out in front of the bridge pin line, the string is essent- ially shorter in its downward excursion than when it is up and bearing only on the bridge pin. A similar thing happens when you have a loose bridge pin. It can also happen when the V-bar is flat and the string cycles over the two edges of the flat. As these two frequencies bounce off the walls nearby, they are in conflict at the point of the mic. You can move the SAT around from one point to another to get a stronger emphasis in the display for one or the other of the two frequencies. If one of the frequencies is at a null point at the mic due to bouncing off opposite walls and meeting at the mic in opposite phase, then you see only one indication in the display. If both frequencies meet equally strong or away from their null points, the display will oscillate back and forth between the two frequencies at the speed of their difference beat. At this point, you can run the cents up to stop the display of the higher frequency or run the cents down to stop the lower frequency display. You will still be able to see the indication of the other frequency, but it will be moving. If I am ever confused as to which frequency I want to tune, I can tune one and then play a 17th below and compare with the neighbor's speeds. I mainly want to use the one which fits with the neighbors best, but sometimes will settle for the one which is the loudest. Jim Coleman, Sr.
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