Forgive me if I didn't implement this feature sooner. I really had no idea the difference could be so drastic. I never owned a Roland MIDI device before, poor me!
Now to enable this feature, you need to override midi section in dospad.cfg with
[midi] mpu401=intelligent mididevice=mt32 midiconfig= mt32.romdir=config mt32.reverse.stereo=false mt32.verbose=false mt32.thread=true mt32.chunk=16 mt32.prebuffer=32 mt32.partials=32 mt32.dac=0 mt32.analog=2 mt32.reverb.mode=auto mt32.reverb.time=5 mt32.reverb.level=3The configuration assumes that you put the MT32 rom files under config directory,
MT32_CONTROL.ROM 65536 Bytes MT32_PCM.ROM 524288 Bytes
Not every game supports MT32, and for those that do, you may need to run their setup.exe to specify MT32 output. You better put such games in its own idos package, to make sure the configuration won't mess up with other games.