Recently I've found a very old
unofficial patch for Dune II that added Gravis Ultrasound support. Unfortunately, that patch does not work well with DOSBox, but the principle behind it allowed me to make a suitable replacement. The simple trick behind the patch is that the setup programme tells Dune II which drivers and sound files to use, so replacing certain drivers with GUS drivers does the job. For the patch, I replaced the Sound Blaster driver with the GUS digital driver, and the MT-32 driver with the GUS MIDI driver. That way, you can use the Sound Blaster Pro for SB emulation if you want to, and you can still select Sound Canvas (which replaces the Tandy 3 voice option) too, although it is recommended that you use the original Dune II setup and sound files if you want Sound Canvas-synthesized music.
To install the patch, simply extract the following files into your Dune II directory, overwriting the old files when necessary (it is advised that you make a back-up copy of the old files first):
DUNE2G.BAT
DUNE.CFG
SETUP.EXE
SETUPENG.DIP
SOUND.PAK
The DUNE.CFG file is already configured to use Gravis Ultrasound for sound effects, speech and synthesized music, so if you do not want to change this, simply run DUNE2G.BAT to play Dune II with GUS music and sounds. For more information, refer to the patch readme file supplied in the package.
NOTE: This patch was made for use under DOSBox, and was not tested with a real Gravis Ultrasound card. There's no guarantee that is will work with real GUS at all.
[Edit] Attachment has been removed. Check the post below for a link to the new version of the patch.