I'm a new subscriber and I've rebuilt many grand players.  We put the
electric pumps in now.  My favorite Amphion some had upside down
valves.  These regulators had a little disc on a stem, held in place
firmly by another stem with a hole in it, tension adjusted by a spring.

Now we throw guts out of old players, but I saved some regulators to put
in uprights. I'm interested in MIDI into old players; and making
roll-up player with levers from old Pianocorder or PianoDisc.

Wayne Boksa

 [ Welcome to MMD, Wayne.  I'm curious about the Amphion devices.
 [ Amphion was the player system manufacturing operation owned by
 [ American Piano Co.  The same man who invented the Ampico, Charles F.
 [ Stoddard, developed and patented lots of devices used even in
 [ competing systems.  The fact that these old devices don't appear
 [ in other player actions, or in later years, suggests only that
 [ some devices were replaced later by cheaper ways to do the job.
 [ I'll bet there are lots of well-designed pneumatic devices in
 [ early player pianos which we seldom hear of.  -- Robbie