Hello All,  If you don't want to build a MIDI decoder the hard way,
I have MIDI Decoders and drivers for a wide variety of musical
instruments.  My products have been used to MIDIfy bells, carillons,
calliopes, AC chimes, lighting controls and other MIDI control
projects.

Decoders are available from 32 to 128 notes, and can be cascaded if
more controls are needed.  I have drivers from 500 ma DC to 10 amps DC
or AC and drivers with mechanical relays with 10 AMP rated contacts.
See http://www.Sound-Research.net/

If you need a custom decoder those are available as well.

Musically yours,
Vern Jones, Sound Research