Do You Know This Sound Card?

The guessing game is back, this time with a twist: I don’t know the correct answer. A generic-looking 1997 vintage sound card recently showed up:

Unknown OPTi 931/941 Card

This is what I call a high-end low-end card… it’s a standard low-end sound card, except it also includes a low-end wavetable synthesizer, which makes it a better class of a Made in China cheap card.

The board has more or less zero distinguishing marks. There is no FCC ID, no obvious model number, no manufacturer designation. A tiny ‘S6159’ near the ISA connector may or may not mean something.

On the other hand, the card is highly recognizable. While clone cards with the OPTi 82C931 integrated audio controller were dime a dozen, the OPTi 82C941 QDSP wavetable synthesizer was anything but common. The 931+941 combination is more or less unique.

The card was produced in early 1997 and also contains a LGS-made (LG Semiconductor) GMS80C501 microcontroller and two MX-branded (Macronix) ROM chips. The ROMs also bear ADMOS copyright and are labeled QS702-1.5 and QS703-1.5 (presumably two halves of a set). The wavetable synth is very likely closely related to ADMOS QDSP 700 and 1000 series chips.

For good measure, this is what the backplate of the card looks like:

Mystery Card Backplate

There is only one audio output plug and the card has jumpers to select between amplified and unamplified output (a not very user-friendly feature of many cheap sound cards).

The card works with generic OPTi 931 DOS drivers, although for some reason the synth won’t produce any audible output until Windows 3.1 plays something over the MPU-401 interface. Some tiny bit of initialization is probably missing in the generic DOS driver. Card-specific drivers might help… if I knew what this card was in the first place.

The wavetable synth is a “real” MIDI device and does not need any TSRs or other special support, it simply responds to data sent over MPU-401. The LGS microcontroller is presumably responsible for that.

So… what is this card and who made it?

Update: As is apparent from the photo, a variant of the board may have existed which also included an IDE connector. The PCB could also clearly be used to manufacture a card with a Waveblaster header, but such card would almost certainly omit the wavetable synth—and could plausibly have been sold under a completely different brand.

Later Update: After staring at the SOUND16.CFG file long enough, I guessed how to make the wavetable output work in plain DOS, without starting Windows first. By default, the OPTi 931 controller’s “synth” DAC only takes data from the built-in FM synthesizer. It is necessary to allow the DAC to also accept data from the OPTi 941 wavetable chip. The FDAC_SRC line in SOUND16.CFG needs to be changed from FDAC_SRC=OPL3 to FDAC_SRC=SHARED. The ‘MIX’ setting could possibly work as well.

Final Update: The card has been positively identified as a Trust Sound Expert de Luxe Wave 32 3D (article no. 09245).

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13 Responses to Do You Know This Sound Card?

  1. calvin says:

    The S2204 marking on the bracket could be a clue.

  2. pdw says:

    Does the card support ISA PnP? If it came with special drivers, it might have some non-default id strings…

  3. Michal Necasek says:

    Yes, it’s PnP, but it just prints some generic OPTi string. And it’s of course possible that there never even were any customized drivers. OPTi was pretty good at providing generic drivers that could have a few strings changed here and there to make them look like the OEM did more than just following OPTI’s build-a-sound-card kit.

  4. calvin says:

    …wait a second, this was approved by the FCC, right? Maybe there’s an FCC ID somewhere on it. Presumably to the right of the European mark on it?

  5. Michal Necasek says:

    There is no FCC ID despite the logo (I didn’t retouch the photo or anything). That said, adapter cards only intended to be sold in Europe/Asia don’t always have FCC certification.

  6. Andreas Kohl says:

    Too many brands were used in the 90s to sell such chinese stuff. And there’s nothing on the backside inidicating the origin? So it could be manufactured by Formoza or BTC and sold in Europe under completely different names. Btw. how it works with OS/2 Warp?

  7. Michal Necasek says:

    Knowing just one such brand would be enough. But I could not find anything.

  8. pdw says:

    I found one similarish card, the Shuttle HOT-237 Spacewalker Sound System 3D wave
    There’s a very low res picture here:
    It has a OPTi 930 + 941 pair, and what looks like two MX-branded ROM chips…

  9. Michal Necasek says:

    Yes, the Shuttle cards are about the closest I could find. At the same time the PCB is clearly different and it’s also using an OPTi 930 rather than 931 controller. Definitely not the same card, although the wavetable synth could be identical.

  10. Kiddo says:

    Looks like an “AudioWave Green” to me…

  11. Michal Necasek says:

    It’s definitely not this: Is there some other “AudioWave Green”?

  12. kylix says:

    Looks like a Trust Sound Expert de Luxe Wave 32 3D:

  13. Michal Necasek says:

    Bingo! The stickers on the underside of the card match (“int. art. nr. 09245” and the EAN). The card shown in the picture also looks like it could well be the same thing. Thank you for solving the mystery!

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