Dave: I hope you received my other E-mail concerning this matter. At any rate I have experience the same problems on the same model piano. I believe the soundboard flexes when the 'big boy" is pulled either up or down that many beats or cents. Whatever the cause it "ain't" stable and I dread the challenge. After all that work I expect it to sound really good and most of the time I'm disapointed. It's most difficult to tune a perfect interval on a moving target. Tommy Black Decatur, Ala.
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