There was an excellent article in an old AMICA bulletin authored by
Jeffrey Morgan and Richard Howe.  As memory serves there were seven
different versions of the Ampico A.  I am not an Ampico expert but do
remember there was an early model with parts made by Standard Action
Co.  Then the more typical versions made by Amphion with the individual
valves held on by clamps.

Earliest ones had what is known as upside down valves and later ones
had right side up valves.  The valve cover changed from a wooden ring
to the type with the press in metal valve cover.  Early stacks had
dowels going through a guide to move the keys while later ones had
flange finger stacks.  The latest flange finger stacks had lost motion
pneumatics to raise all the fingers when the soft pedal was on.  The
latest A expression mechanism had a small pneumatic to compensate for
the sustain pedal pneumatic raising the weight of the dampers off the
piano action.  I have also seen late A models with a different
amplifier on the pump somewhat like a B model.

There were several versions of the B Ampico.  The two most common
references are to what is known as the full B and the half B.  Mason
& Hamlin, Knabe, and Chickering all got the full B with everything you
would expect a B to have.  The other pianos usually got a B stack
without the individual note pneumatics having the little fine
adjustments for the softest playing.  They also were missing some other
parts that made a B so nice that I can't remember right now.

Many of the these other pianos were produced with the B drawer and
an A stack with A expression during the thirties.  Once again I don't
remember all the fine details but, if you want a B Ampico, your best
chance of obtaining a full B Ampico would, of course, be the Masons,
Knabes, or Chickerings.  I don't remember seeing a full B Ampico in
any other brands.

Of course I guess that there are exceptions such as the Steinway Ampico
B's that show up very rarely.  In the past there have also been retro-
fits by restorers using components to build an Ampico.  One example
would be the Mason and Hamlin seven foot grands that have been retro-
fitted by restorers with B drawers and A parts.  There is only one
original known seven foot Ampico B with all its original parts.

I would suggest anyone wanting to know more that they consult the past
AMICA Bulletins.

Don Teach, Shreveport Music Co
1610 E. Bert Kouns, Shreveport,  LA  71105
dat-smc@juno.com