Hi Jim, I'd be most interested in studies of the Jorgensen effect: unisons which go flat as the 2nd and 3rd strings are tuned to the first string. Roger Jolly wrote his own observations and measurements of this on pianotech, a long time ago. Sanderson co-taught a class with Jorgensen investigating the effect, but I skipped the class(es). I think it was either at Reno or Chicago (2001 or 2002). I don't believe Sanderson's findings were ever published. Patrick Draine
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