This is ConSiGno's OPL instrument patch table, found here:
<https://github.com/sneakernets/DMXOPL>
This is the result of many years' development and probably the
highest quality Doom OPL instrument set that's ever been developed. I've
obtained permission from ConSiGno to submit it to Freedoom, with the
following small omissions from the upstream version:
* Instrument 107 (Shamisen)
* Percussion 36 (Bass Drum 1)
* Percussion 69 (Cabasa)
* Percussion 76 (Hi Wood Block)
* Percussion 77 (Low Wood Block)
In doing due diligence I found that the patch data for these instruments
matched the patch data from Doom's GENMIDI table. Just to be
meticulously safe we'll keep the old versions of these (nothing, in the
case of the Cabasa). Other than these, every other instrument has been
replaced with a new patch.
This music sounded really horrible with Freedoom's GENMIDI lump, which
was a shame because this is a really beautiful level. So adjust a
couple of the more prominent instruments used for this music track:
* Instrument 104 (Sci-fi):
This instrument was using a frequency multiplier that put it 2
octaves and a 5th above, making it (intentionally, because it's
a "sci-fi" effect?) discordant. Rework this so that it isn't
discordant any more.
* Instrument 51 (SynthStrings #1):
This had a slow attack phase which had the effect of offsetting
the notes slightly, so that they seemed out of sync. Adjust this
and also increase the feedback so that the instrument sounds more
"stringy" (?)
