Hello again!  I'm re-joining the list after a 2-year absence.  While
I don't own any pneumatic mechanical instruments, I remain very
interested in them. I have owned several solenoid-based reproducing
pianos; currently I have a Yamaha C-7 (7'6") with the new Mark III
Disklavier (which you can see at http://www.robert.to/newc7.html).

I've also worked on several projects to build electric solenoid
percussion instruments: triangle, snare, castanets, etc, to play along
with the solenoid piano.  I programmed a 17C42 microcontroller to decode
MIDI and fire the solenoids.  Some details on the microcontroller
I used are here at http://www.swixo.com/midipic/

I work for Walt Disney Imagineering's R&D group, though my interest
in mechanical musical instruments is (mostly) a hobby.

Robert Swirsky-Warner