natt
Junior Member
Posts: 248
Registered: 05-11 |
Porsche Monty said:
The current approach that Doom source port developers have taken regarding OPL emulation is rather relaxed, maybe because most players don't care for it.
It's said that the emulated OPL is pretty much the same (if not exactly the same) as the original at software level, so that's unlikely to be the problem here.
Then we have each source port's particular implementation of the OPL emulator which are in fact, flawed to varying degrees. This results in notes being omitted, played incorrectly, etc.
However, what I consider to be the real problem is "authenticity" (or lack thereof) due to nonexistent DAC/filter emulation. Without it, you're left with that horribly FLAT sound.
Maybe it would be a good idea to consider expanding OPL emulation in that direction.
Vibra16's filtering, now that would be amazing.
I don't have a horrible ear or anything, but the problem for me is, if I listen to OPL emu playback and I hear something that doesn't sound "right", is it:
a) Bad memory (I last played vanilla on an OPL in 1998 or so)
b) Problem in the OPL emulator itself (which is an opaque black box as far as I'm concerned, lotsa code there)
c) Problem in Chocolate OPL Driver code
d) Inherent OPL limitations (in particular, 9 voices with some instruments taking up 2 voices each means that even a perfect setup can have massive dropout compared to a general midi synth which has 24 or more voices)
With all of those possibilities, and the basic design problem that the OPL emulation is not trying to be "right", it's trying to be "wrong like vanilla", I don't even know where I'd start to fix things. And as far as this filtering you're talking about, I bet it varied widely from sound card to sound card. Add in the horrible frequency response of early 90s desktop computer speakers, and everyone is going to have their own idea of how OPL should sound.
So the end result is that prboom-plus OPL sounds exactly like chocolate doom OPL. Well, at least I fixed the tempo bugs.
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