[ In 010212 MMD Dan speculated on solenoid piano players: "They'd
 [ need to handle upwards of 1500 watts to give a concert performance!"

My remark about electrical pianists needing to have 1500W under their
belts seems to have sparked off an interesting new thread.

I base this estimate on the 1913 65/88-note Pianola pushup very heavily
rebuilt by Peter Davis (Loughton, North London) in 1984 to play Duo-Art
rolls in a concert environment.  The conversion makes an immensely
heavy instrument and the pump unit is separate, being furnished with
80 feet (25m) of 1-3/4 inch (42 mm) plastic pipes to connect it to the
pushup.

I don't have exact details for the motor but it looks like a large
synchronous one such as are used in commercial freezer units.  On
several occasions I have been appointed as pump minder in concerts.
(I'm there, really, to prevent terminally bored orchestral players
tampering with the pipes.)  With heavy playing up above on the stage
the motor gets quite hot, and I would guess its drain is then
equivalent to at least 500 watts.  It would follow that momentarily,
at least three times this would be required to play a heavy chord.

What's more, the Davis set-up is only just powerful enough to produce
adequate sound from the piano when circumstances are against it,
typically when curtains back the instrument (Purcell Room, South Bank,
London) or the piano is soft-toned (Dome Theatre, Brighton).  In fact,
I've never known it be too powerful.

Concert use of player pianos or piano-players requires their power to
be turned up very considerably.  Anyone who has been in an average room
with a concert pianist practising will have been surprised by the power
they employ.  Students introduced to a Steinway D in a large hall for
the first time suddenly have to learn new tricks and develop their
wrists.

In the famous "Barden Interviews" in the AMICA Bulletin, where Nelson
Barden talked to those involved in recording for the Ampico, it was
recalled, I think by Milton Suskind, that when Hickman's spark
chronograph first enabled the editors to measure what was really going
on in a recording session, everyone was astonished to find that Ampico
rolls had been going out since 1911 set to give playing barely over
half the power that the original pianist had used.  A machine, it
seems, does not command the attention and respect of a celebrity
performer, and so is expected to moderate its enthusiasm.

Thus when rolls are to be played for earnest in a large hall, this
process must be reversed, or the whole thing will sound impossibly
lacklustre and pusillanimous.  Expanding the dynamics for concerts
of the 9-foot Weber player grand in Aeolian Hall, London, was referred
to as "Knightleyizing", after the hall manager who had to organize it.
When the Davis push-up player is used in a normal room, the pump has
a resistor switched in and the "power-15" settings on the accordion
valves are changed.

Thus powers usual in domestic situations can't be used as a yardstick
for concert requirements.

Dan Wilson, London