Vertical backcheck noise?

[Joseph Garrett]

Try putting a couple of drops of 50% -50% Hide glue and water, (distilled is
best), on the back catch stem area and the area where the stem goes into the
butt. Your putting a piece of felt between the check and the catch may
simply reduce the energy going through the stem. Masks the area shock
absorbsion, but gives a false idea where the noise is coming from. Anyway,
give it a few minutes and then try the note again. Should tell you where the
noise is coming from. If there's still the noise, then I would suspect loose
catcher wires in the catcher head or in the wippen. There is also the
possibility that it has some thin backcheck felt that is too hard. On pianos
around the 70's, some manufacturers  started using this weird stuff and it
is noisy.
Best Regards,
Joe Garrett, RPT, (Oregon)

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