This program takes MIDI through midi0 (serial port A on NeXT hardware)
and uses it to play the "Pluck" instrument (SynthPatch) on the DSP.
The keyboard's velocity is used to scale the brightness of the
synthesis. Pitch bend is handled.  No other MIDI parameters are
currently supported by Pluck.

Note that the SynthPatches supplied in the Music Kit SynthPatch Library
are not optimized for keyboard performance. We hope to provide versions
specially-designed for keyboard performance in the near future.

