I want to respond to Julian Dyer's article on converting an electric
Duo-Art to a foot pump Pianola.  I will agree with you that you are
describing the way Aeolian, the world's largest manufacturer of musical
instruments did it, with hundreds of pianos on the assembly line and
teams of technicians able to think up and then create, and then improve
all kinds of mechanisms.  To tell Doug Wendell that he should do it the
same way Aeolian did it assumes Doug has such unlimited resources at
his disposal.

I will admit that I forgot about the spill valve in the electric
expression box, but that is easily enough taken care of.  Simply tee
an on-off valve into the four lines controlling the theme accordion,
and you are done.  Now, when you start to pump, the theme accordion
collapses, closing the spill valve.  Now, the only way to control
the volume of the theme is by your pumping -- exactly what Aeolian
intended.  The volume of the accompaniment is controlled by the key
slip levers, exactly what Aeolian intended.  An additional valve will
turn off the snakebite holes in the tracker bar, so that playing Ampico
and Welte rolls will not accidentally trigger the Themodist mechanism.

Julian Dyer was giving instructions on how to make Doug's piano look
and work like a factory original Pedal-Electric Duo-Art.  I was giving
Doug a quick shortcut to get the same results with a minimum of work.

Randolph Herr