I've installed Coolsoft VirtualMIDISynth and MIDIMapper, and downloaded and set up a soundfont. It works fine in Crispy Doom; and I can use it in Dark Forces by running its Setup.exe and selecting "General MIDI" as the music device. But Duke Nukem II and other Dosbox games still just play regular Windows MIDI.

I found a guide that says to run "mixer /listmidi" in Dosbox to get VirtualMIDISynth's device ID, then set the "midiconfig" variable to that ID in the .conf file (here dosbox_duke2.conf). But that doesn't work either.

Anyone have any suggestions?

Akalabeth 1998; Cosmo's Cosmic Adventure; Master of Magic Classic. On further testing, though, The Elder Scrolls: Arena works. The VGA version of Quest for Glory works while the EGA version doesn't, despite both launching from the same Dosbox instance. Is that consistent with your understanding?

I assume that that at least means that the music never sounded any different; so I'm not missing out on anything.

(I got an error message about a missing device or something when I launched Akalabeth earlier, but I haven't been able to get the message to recur. It might have been a temporary problem from doing something wrong, or not having launched MIDIMapper yet or something.)

With my original Ultima Collection CD, Akalabth's sound.cfg file needs to have the following 2 settings set to these values: I don't have Cosmo's, but it's likely another adlib music situation.

Master of Magic Classic (official )is a bit annoying to set up due to the GOG launcher solution. But you'll need to run DOSbox.exe from the Master of Magic Official Release\DOSBOX folder. Then type the following in the DOSbox window: Then choose General MIDI for the music card and sound blaster pro (later) for the effects.
You should then be able to use the launcher to play.

Running Quest for Glory EGA install.exe shows that MT-32 plus Soundblaster is the best music option, General MIDI isn't an option here. For the older MT-32 games you'll either need an actual MT-32 device and/or emulation if you want the best music quality.