My 5'4" Knabe Ampico B (Louis XV), serial no. 107030, has drawer
date stamp 7/29 so I believe it is a from quite early production.
It has always sounded louder on 2nd amplification than any other Model
B I know.  It gives me the impression that the hammers are being driven
too hard against the strings.  I have Ampico A and Duo-Art pianos, so
have a fair idea of how they typically sound in my home.

I have wondered whether my piano has higher pump pressures than later
instruments.  Water gauge pump pressures using the test roll are 16",
24" and 37".  All amplifier tests, up and down, appear to operate per
test roll.  New Abel hammers ("medium hardness") are fitted, with not
much change in loudness from the originals but significantly better
tone.

Is any adjustment possible, or alternative pump spill spring available,
to reduce the pump pressures on 1st and 2nd amplification closer to the
minimum 21' and 30" per the test roll info?

This much-loved piano is in Melbourne, Australia.

Harold Ball
Melbourne

 [ The "factory spec" Ampico B plays _very_ loudly at maximum crescendo
 [ or 2nd Amplification.  See the "Ampico B Intensity Scales" reproduced
 [ at http://www.mmdigest.com/Gallery/Tech/Ampico/amp21.htm  To reduce the
 [ sound level you can install a weaker pump spring (thinner wire) of the
 [ same length, while preserving the 2:1 change in tension.  -- Robbie