I agree with Deane Shepard saying that a tuba operated by a MIDI
controlled mouthpiece can produce any note without the need of
fingering [18.07.27 MMDigest].

I wanted only to underline that, without fingering, only some
notes will be in resonance, and most of them will be out of resonance,
so that the timbre and volume of the various notes will be quite
different.  The sound produced will be quite different from a human
performance, where the player would set in resonance every note.

In my opinion, mechanical music should try to imitate as closely
as possible a human performance.  It would be very easy to get this,
by simply operating the valves by MIDI-controlled actuators.

Leonardo Forti
Rome