You need to update the game.

Support for EAX 4.0 was first introduced with patch 1.3.

Joseph_Joestar wrote on 2024-10-07, 07:48:

You need to update the game.

Support for EAX 4.0 was first introduced with patch 1.3.

I see, thanks a lot! I read somewhere that 1.3 made the game run on newer versions of Windows, but couldn't find any patch notes on EAX. I'll try that!

Here's an archived version of Creative's old website which has the EAX related patch notes. Relevant bits:

Creative Labs wrote:

Doom 3 The Way It Should Be Heard! Creative has collaborated with ID Software to bring its customers the full Sound Blaster expe […]
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Doom 3 The Way It Should Be Heard!
Creative has collaborated with ID Software to bring its customers the full Sound Blaster experience - real-time EAX® ADVANCED HD™ effects processing, fully hardware based 3D mixing and full hardware based audio anti-aliasing...Doom 3 has never sounded so sweet!

With the latest DOOM 3 patch you get full support for all the above, thanks to a custom OpenAL based audio engine. Creative sound card owners can now experience the thrills and chills of this awesome game with fully immersive audio, and with no frame rate hit! Run Doom 3 in 7.1 mode at just the same framerate as the software based 2 speaker mode!

EAX ADVANCED HD
Every level of the original Doom 3 game has been enhanced with real-time EAX ADVANCED HD effects. Now experience the spine chilling atmosphere with a whole new dimension, as realistic environment effects are applied on the fly. For the new Doom 3 expansion pack "Resurrection Of Evil", we take it to the next level. Each map has been designed with EAX 4.0 multi-environment technology for the ultimate audio experience!

Hardware based audio anti-aliasing
Doom's internal audio architecture utilizes audio effects that run at a 22.05kHz sample rate. This offers a good compromise between audio quality and sample size. With Doom 3's native audio engine, these audio effects are then upsampled to 44.1kHz on playback. While this design yields good results, the Creative Sound Blaster implementation brings its hardware based sample rate converters into play to make it even better. Any software based SRC process has to balance the tradeoff of CPU versus audio quality. As a result, linear interpolation is usually used for upsampling, with the downside that "audio jaggies" tend to occur - slight distortion or coloration of the original signals. Creative's hardware DSP deals with this by applying 8-point interpolation as part of the SRC process - "audio anti-aliasing"! The result is smooth, high quality audio every time.

The EAX patch was a joint effort between Creative Labs and id Software.

Thanks! Updating to 1.3.1 fixed it. Interestingly, I also needed to put my console in Game mode as opposed to Entertainment which I prefer for its cleaner interface. Otherwise it said that no supported hardware is found.