[ Ref. Mark Reed in 220914 MMDigest ]

Hi Folks, Organ Supply Industries has a special valve for player
pianos. It's not like their pipe valve and not like the very similar
action valve which has external mechanical parts.

It looks sort of like the coil part of those valves but with a metal
tube on the end, onto which you put a rubber tube. When you apply
a voltage to the valve, it opens the tube to ambient air. It should be
just the thing for other MIDI applications. I don't have the current
price but I suspect that it's quite reasonable, like their other valves.

Regards,
Craig Smith