To Hazen Bannister and others: I have written a couple of articles in the Journal back in '97 in regard to stretching the center octaves more by altering the A4 stretch number. The articles explain the math necessary, but in general, you can get more stretch by adding perhaps .5 cents to the measured stretch number for A4. After you do this, you can play the tuned A4 while looking at the A3 setting of the SAT. If the LEDs are moving about two lights per second, this means that you have an octave spread in which an F3-A4 M10th will beat about 1/2 bps faster than the F3-A3 M3rd. There is only one caution: When you get up to C5, you need to add offset to the SAT by the same amount which you added to the A4 stretch number. FAC tuning usually spreads the Bass a little too much for small pianos since they were originally computed to satisfy Concert Grands (and they do). So one can lower the stretch number for the F3 and avoid having to do the direct interval tuning of the Bass which Farrell has mentioned. However, it might still be well to do a little direct measured tuning around B2 and down a little ways because this is where the SAT starts listening to stretched 6-3 type octaves instead of stretched 4-2 type octaves. As an example, when tuning a GH1 Yamaha grand, it is good to tune the B2 by noting first the deviation values of C3 and C#3, then placing the SAT into the TUNE mode before going to the B2 so that you can estimate the lowering of the B2 by the same additional amount as was used between the C#3 and the C3 in MEM mode. This will guarantee a smooth transition into the upper Bass from A#2 on down a little. After a few notes into the Bass one can then revert back to the MEM mode using the FAC provided curve. One can then utilize the direct tuning mode, but keep the curve more or less even by putting in a little positive offset whenever playing the upper note of an octave shows the LED rotation tending to move in the sharp direction while the SAT is set on the lower note of the octave. By using a little positive offset, this will shrink the 6-3 octave (ie raising the lower note of the octave) just a little from the normally stretched 6-3 octave which FAC produces. Some people may prefer more stretching in the Bass than the FAC provides normally. This can be accomplished by gradually applying more and more negative offset as you go along downscale. I do this when tuning A Bosendorffer Imperial, but never on a small piano. Jim Coleman, Sr.
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