Hi Everyone,  I'm just now getting done here with another Model B
Ampico in a 5'4" Knabe.  I shot a video showing the operation of
the pump amplifier with second and third amplification and thought
all the Model B enthusiasts would be interested in seeing it.  It
really is quite an ingenious invention!

https://www.youtube.com/watch?v=xrfldADFF4M 

Ben Gottfried - Ben's Player Piano Service
Richfield Springs, New York
http://www.bensplayerservice.com/