What is considered to be an "acceptable" vacuum level ( inches H20),
for the average player piano chest?   That is to say the difference
between "perfectly sealed" and the actual reading....

Gerry Ceccarini

 [ An energetic kid can overcome a lot of leakage in a pumper.
 [ However, the performance of a reproducing piano will suffer.  I'm
 [ not sure just how this might be measured; air flow is "cubic feet
 [ per minute", or similar, and that would be the units for leakage.
 [ Maybe an old residential natural-gas meter could be used...
 [ -- Robbie