I wrote this and then someone pointed out that the discussion is probably about "why FM rather than wavetable" but I'll post it anyway 😵
AWE64 and some SB16s and AWE32s use the Creative clone chip called "CQM". It definitely sounds a lot different from OPL3. Basically you either:
1. Don't like it and prefer real Yamaha
2. Can tell the difference but don't care
3. Can't tell the difference and remain in blissful ignorance
4. Hate the sound and want to burn every Vibra 16 in the fires of hell as a result
5. Actually prefer it to real Yamaha.
All of these are legitimate; I fall into category 1 (see, this is why VOGONS needs polls!).
A lot of people really like the sound of an actual OPL3; it has a richer, warmer, deeper quality to it. But it's always completely subjective.
Then, of course, like you mentioned, there are a lot of PCI cards that don't have any sort of FM chip at all and try to emulate it using the wavetable, which usually ends up sounding like a bad nightclub band playing music in a fishbowl.
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