I'm also checking out potential candidates for a RPi solution offering me MT32 & GM Midi for my (Sharp X68000) retro gaming needs. I came across:
WavePI, on this forum
PatchBox OS
Zynthian

Zynthian is the most end-user friendly solution it seems, but has no MT32 on it. Wondering how easy/hard it is to integrate it in the whole Zynthian experience as well.

claesbas wrote on 2019-04-28, 16:17:

I have searched but did not find anything about the Zynthian hardware that looks (perhaps a bit overkill and expensive) like a v […]
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I have searched but did not find anything about the Zynthian hardware that looks (perhaps a bit overkill and expensive) like a very interesting hardware for MT32 and GeneralMIDI synth emulation.

Have anyone seen that project before? http://zynthian.org/

Would it be a good hardware for this?

http://shop.zynthian.org/shop/product/zynthia … -225?category=1

250 euro is a lot for this yet - but its a nice kit that could be used for much more and resold and used for other things...

Zynthian hardware can be used for running MUNT, by preparing dedicated microSD with Raspbian/MUNT on it, and it plays MT32 midi files well. But i have not tested MIDI communication