Hello everyone, I'd like to bring to your attention this project of mine.

MIDIplan

Realtime MIDI sequencer to play General MIDI (i.e. DOS games) on older non-General MIDI-compatible synthesizers.

An MCU-based board to which you plug your DOS MPU from one end, one or more retro MIDI synths from the other, and sound comes out.

Current status:

what it does already

1. Program (instrument) remapping.
2. Channel multiplexing.
3. Device-specific sysex support for bank switching etc.
3. Controller values tracking and restoration.
4. Transposition (also layering).
5. Volume/velocity change.
6. Program routing to different devices. Helps with dedicated drum machines for example.
7. Program load balancing, when there is more than one identical device present.

Currently supported devices:

1. Yamaha EMT-1
2. Yamaha EMR-1 (drum)
3. Yamaha FB-01
4. Yamaha DOM-30
5. Casio CSM-1
6. Kawai PHm
7. Kawai XS-1
8. Zoom RT-234 (drum + bass)

Demo recordings:

https://youtube.com/@MIDIplan

*) there also are recordings on General MIDI-compatible synths there, for reference and fun.
**) got a lot more, will be publishing gradually.

Source code:

https://github.com/targeted/midiplan

Directions to improve:

1. Add support to more MIDI synths.
2. Add UI in a form of LCD with buttons or what have you.
3. Design a custom board, put in in a case, have a product.

Please feel free to contact me at dmitry@targeted.org

Thank you !