Help !! I'm doing work on a Kroeger player piano that was about 160 cents flat. I made 2 passes on my SAT III using the pitch raise calculator feature measuring octaves at all of the A's and recalculating the pull. For some reason I am getting a gong like sound in one of the octaves . Other parts of the piano sound fine
C#3 the first triple string unison sounds wild even though each string stops the lights when tuned alone. Starting at F5 including G5; G#5 A5 and B5 all sound like gongs or tubular bells.
I know the piano needs more pitch work but I wanted to equalize the tension and bring in the unisons. I have done this many times in the past with no problem. Could it be bleed through or sympathetic vibrations from the upper partials ?

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