Many thanks to Mr. Bullock and others for their advice on my project.
A bank of pouches sounds feasible, and it would eliminate quite a few
moving parts.

Mr. Bullock, I think I understand the concept, so let me see if I am
clear on this.  A bank of pouches with maybe a small, light metal lifter
disc?  Then when the pouch goes up it makes the connection to the two
wires for that note?

My MIDI strip has a [conductive] rubber plunger to make the connection,
very similar to the computer keyboard.  I will remove this today and see
how many connections will have to be made per note -- probably two.
I don't know if the MIDI strip has a "common" to each note.  If not, both
contacts still could be made in each pouch.  I don't believe arcing will
be a problem here since the voltage in a MIDI strip is extremely low
compared to a relay.

How about two screws per note through the top board for the metal lifter
disc to make contact with and to connect the wires to?  This way
the "travel" could be adjusted.

I believe I need to go to St. Louis and Visit you.  I am only 135 miles
from there.  I will let you know in advance.  I own my own electronics
business and it is sometimes hard to get away.  Anyway let me know if
I am on the right track.  This weekend, I am going to experiment on this
and see if I can work out something.

Andy Taylor
Missouri

 [ Editor's note:
 [
 [ The rubber plunger in the MIDI keyboard is conductive rubber; as
 [ it spreads across the base contacts the conductance changes in propor-
 [ tion to the distance the key is depressed.  The time-rate-of-change
 [ then becomes the "MIDI velocity" data which controls the loudness of
 [ each note played by the MIDI playback device, either a synthesizer or
 [ a solenoid piano.
 [
 [ Just like computer keyboards, a lot of trial-and-error experimenting
 [ went into the development of synth keyboards, and they are now *very*
 [ rugged and reliable.  (Yes, my Roland keyboard was anointed with a
 [ pitcher of beer, and survived!)
 [
 [ Perhaps you could devise a pouch to directly operate the rubber plunger,
 [ Andy.  It would be a novel and reliable way to convert the pneumatic
 [ signal into a complete electric MIDI signal.
 [
 [ -- Robbie