Terry, EXACTLY! You really hit a large nerve with me. Your, (son's), experiment pretty much tells the story. I've been preaching the pitch raise situation with Square grands and Bird-cage pianos, forever. If a piano is tuned to it's "designed pitch", it will stay better in tune. This is due to tuning pin "cant", structure compression, etc. If the strings will take the tension. . . go for it! Regards, Joe Garrett, RPT, (Oregon)
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