Hello,
I am almost definitely sure, that at least some of my AWE32 is outputting stereo, while sound settings are done as "Sound Blaster Pro".
What should I look here, since I remember reading (here in Quest Studios most probably) that AWE32 cannot do stereo while acting as SBPro?
Is it then so, that the midi (OPL3) cannot play as either SBPro1 or SBPro2?
I was playing the good old Wolfenstein 3D, when I noticed the stereo sound (opening doors while facing 90 degrees off). It might be the good old CT2760 which I was/am using, I can check after some discussion if needed (the reverb + chorus is seen as bars with the mixer setup in bootup).
The SB16/AWE is totally downwards compatible with the SBPro1/2 as far as OPL music goes. Stereo OPL will work fine on any SB card with an OPL3. When it comes to digitized sound, it is not so downward compatible. The SBPro 1/2 Mixer has a mono-stereo switch that the SB16/AWE mixer lacks, and the SBPro 1/2 and SB 2 DSPs support output transfer modes that the SB16/AWE do not. You may be stuck with mono digitized sound if the game does not support the SB16/AWE cards.
However, in Wolfenstein 3D, this is not the case. You will get stereo sound even with an SB16/AWE. First, let me quote the erroneous explanation:
SB16 Isn't a Pro
One of the more subtle reasons Wolfenstien 3D was such a success in 1992 was because of the way it handled sound on a Sound Blaster Pro: When an enemy was to your right, you heard him on your right; when a shot was fired off to your left, you heard it on the left, etc. It was one of the first true immersive stereo experiences, and also helped you play the game better because you had an audio clue as to where the enemy was.
If you've tried to play this game (or any other game that supports stereo sound on the Sound Blaster Pro) on your modern sound card, however, you've probably noticed that it's not in stereo, which detracts from the fun. You're not going deaf; it really isn't in stereo. Here's why: Most modern sound cards are either the Sound Blaster 16 or clones of the Sound Blaster 16. The Sound Blaster 16 is backward compatible with earlier versions of the Sound Blaster, with one exception--the on-board mixer. The Sound Blaster 16 improved the on-board mixer of the Sound Blaster Pro, giving it finer control over volume levels and automatic gain control. What they forgot to include was the filtering system, which had two functions: A high-pass filter that muted the sound, and a stereo/mono filter that controlled whether or not the output of the card was mono or stereo. To do stereo sound, the Sound Blaster Pro would initialize a 44100Hz digitized output stream, then flip the stereo/mono filter bit, which converted the output stream into 22050Hz stereo.
Without this filter, modern sound cards initialize the 44100Hz mono stream okay, but then do nothing when the stereo/mono filter bit is flipped--because it doesn't exist. So you're left with mono sound. There is no way to fix this problem without switching to a sound card that says it is explicitly Sound Blaster Pro compatible.
A small footnote on this issue: When I discovered this, I felt cheated by Creative Labs and called them up to complain. They responded by asking me to look at the box and find where it said it was Sound Blaster Pro compatible. I couldn't find it! Damn those marketing people! You'd think that a new product in a product line would be compatible with older versions of the product... Well, the box did say it was 100% Sound Blaster compatible, and it was--with the original Sound Blaster only.
Now for the accurate answer:
Wolfenstein 3D's digital sound effects do play in stereo on an SB16 because the Stereo effect is realized by playing a mono waveform and just changing the mixer volume of the left/right channels of the DAC part. What the SB16 does NOT support is putting the DSP itself into stereo mode the SBPro way, which is not used by Wolf3D.
What Trixter is writing is basically correct, but it does NOT apply to Wolf3D (at least to any of the versions I have).
Wolf3D's FM music on the other hand is always in mono on any card. If you look at the .IMF music files, you'll see that they don't access any of the OPL3's extended registers.
