Licentious Howler wrote on 2025-08-07, 21:03:

This is with an Aureal Vortex 2, 2041 drivers, and it sounds effectively the same with headphones, satellite, or quad speakers.
Is there anything I can do to potentially disable this short of reverse engineering and hacking Thief or the A3D API?

I don't remember the exact details, as it's been a while since I last tested this, but I think Thief worked slightly better with an older version of Vortex 2 drivers. Something like 2015, as I recall.

It's also possible that subsequent patches improved this. Check the patch notes to see if there's anything sound related there.

Thanks for that suggestion, I've actually never used an Aureal driver version earlier than 2040 in my life, never knew some games can actually work better with the prior ones, so I gave it a try.
Unfortunately, 2015, 2031, and 2035 all seem to exhibit the same intense muffling under the camera behavior, unless there was just some setting I missed. (I even gave 2048 a whirl, but that just locked up my entire PC when spawning into the map, classic 2048 behavior 🤣)

I also patched up and tested Thief 1.33 and unfortunately that did nothing to change the elevation filter quirk, and while I didn't expect a change, it also doesn't add in dithering into the renderer... unless it's just some problem that uniquely breaks down on Nvidia FX.

I wonder if this really could be the experience that people just always had with this game's A3D and maybe I'm just more bothered by the elevation filter than others.

Edit: as a bonus, it looks like messing around with those old A3D drivers has somehow inexplicably truncated both channels of my rear speaker audio into just the rear-left speaker, lovely.

Alright, I didn't actually realize the "2000" driver was the first for Vortex 2--I wasn't looking carefully enough in my directory and thought it was a driver for Windows 2000 oops, hah.

And as it happens, this actually solves the filter issue for Thief! It sounds more like you'd expect now, and the hardware accel definitely sounds like it's still doing everything it's supposed to, since the "speaker test" panning is more gradual, and you can hear a (subtle) filter when sounds emit from behind you.

It's unfortunate that this driver appears to be limited to stereo speakers, but it's understandable given how it appears like there weren't even card variants with rear speaker outputs at first. It may have been precisely the code that allows for quad speakers that introduced this issue for all I know, but it still is unfortunate that 2015 couldn't have just worked and let us play in quad. At least it didn't turn out that you require a Vortex 1!

I didn't initially mention this, btw, but I also had the elevation filter strongly in Thief II and System Shock 2, but I wasn't sure if we could just chalk that up to "yeah but these were made with EAX from day 1, so that's why the A3D sounds bad"--Thief 1 obviously is a different story. At least in System Shock 2 1.15, this Aureal 2000 driver also fixes the filtering problem. However, Thief II crashes any time it tries to access hardware accel. That is Thief II 1.18, however... there is a possibility that the old release build might play nice.

As for the lack of dithering in Thief 1, I have found a YouTube video that was high enough quality I could make out dithering on a Voodoo 2, so suspicions confirmed that LGS devs probably just tested this on Voodoos and they saw pleasant dithering, and other cards likely weren't tested as much or the lack of it became a "known shippable". I guess I should go through the other cards in my bin and see if I get lucky, but it is a shame they definitely won't have the horsepower for anisotropy and AA, and almost certainly won't have digital output.

(Update: My Matrox G450 and ATI Radeon 9200 Pro didn't do anything different in this regard)

(the speaker truncation problem seemed to just go away after some driver reinstall, dunno' what that was about)