It's one or the other and you'll have to do what that thread talks about and enable/disable the card you won't be using.
They can coexist but will not work in tandem together.

The solution is a Turtle Beach Santa Cruz, or Game Theater XP which use Sensaura on the CS4630 DSP and will allow you to have both EAX and A3D running. Although the final effects may sound different.

All A3D.dll emulations will just enable basic HRTF in games supporting A3D. The HRTF may sound different than a Vortex 2 running the same game.
There aren't many downsides to Sensaura running on those DSP's, it was always a really good technology.

Tb santa cruz supports a3d 2.0?

Yes and no, it isn't a full supported emulation/re-implementation of A3D 2.0, but it does make use of the geometry exposed by the games designed for A3D 2/3.0

When a game is designed for A3D 2.0's WaveTracing, a second smaller subset of level geometry is provided for WaveTracing to calculate reflection bounces off of. Sensaura takes this geometry and does it's own Chaotic WaveTracing which should technically be better than WaveTracing's approach, but Chaotic WaveTracing doesn't seem to be implemented/working in any A3D 2.0 titles, Sensaura will make use of that extra geometry for proper occlusions though. [edit] Actually it might work in the Win98 VXD drivers of which I have not played with much, I've always used the later WDM ones...have to test this out later
Sensaura's HRTF algorithms are pretty accurate as well and can be tuned to the individual.

I'm a big fan of Sensauras work, if Creative never acquired them either, we would at least have their support on motherboard audio CODEC's for 3D like we used to.
🙁

I saved all the Sensaura docs before they went down...here is the one about Chaotic WaveTracing

so if I take for example a ESS Canyon3D, how to know when it will use Sensauras HRTF? Do i need to turn on this option somwhere in the drivers? Or do Sensaura convert A3D signal automaticaly?

Automatically, however what I read about the Canyon3D is that it isn't a full Sensaura accelerator and doesn't have DSP code written to offload the processing, which means it will render in software and not work/sound as good and it running on the CS4630 DSP's 🙁

A mirror case of A3D reimplementation vs running on the actual Vortex chips, the real thing just gets the job done better in the end.
The CS4630's were designed to fully support all of Sensauras features, every other DSP fall back to Software rendering.

I do like reading older articles about these cards, it seems every sound card manufacture basically makes a claim to designing "The worlds first! 3D audio accelerator!", ESS Canyon3D is no exception 😁.
Those of you who actually own one, tell us how it sounds and how well it worked.

BIG Thanks for help! 😀

And btw. How is the legacy windows "command prompt" support on CS4630? Does it have high compatibility with games like ESS Solo-1 has?

I don't have one, but I've read (here and elsewhere) that CS4630 under DOS isn't good. That's why I don't have one, primarily. I'll let others chime in who have actually used one.
All CS4630-based cards I've looked at don't have a PC/PCI connector, and that means that for DOS support they must use either DDMA (if the motherboard supports it, many don't) or a TSR.

Still we have to distinguish between "Real DOS Mode" which is the boot option without windows shell, and "Windows DOS box" which is DOS "command prompt" box i Windows shell. Im speaking about the second option - DOS in a window. These are totally different things if we take compatibility" into account. For example my YMF724 on Conroe865PE motherboard works good under "Windows DOS box", but under "real DOS mode" i can't even initialize it.

The thing why I'm asking about "windows DOS box" compatibility is because I have another machine for early DOS games, where there is only DOS installed, so I'm playing the oldest games on it. But there are lot's of "late DOS" games which I would like to run on my Win98 machine without "restart in DOS mode" - it's just comfortable for me. Thats why I'm looking for a card with the best compatibility in windowed-DOS.

Agreed, that's why I only commented about the potential "real DOS" compatibility problems.

As for the YMF724, have you tried using the DSDMA TSR under real DOS? I think I've seen reports of it allowing YMF7x4 cards to work on chipsets without PC/PCI or DDMA support.

Yes i tried it. It hangs my PC. The BIOS lacks ISA/PnP settings. There is no way to control PCI bus on Conroe865PE. Theres also no difference in which PCI slot i put the card.

The Santa Cruz's SB emulation DOS TSR is awful, it's in it's own tier of bad emulation 😉
I haven't tried it under DOS in a window (dosbox is actually the official term).

But when it comes to EAX2 and 3D audio support it's up there and contends extremely well with a Live and Vortex 2.

OKay just tried the Santa Cruz windows dosbox OPL3 playback, and I threw up. It's the same as DOS and so wretched that it definitely deserves it's own category of awful OPL3 emulations. 😉
Still love the card though, perhaps it can be updated also in the future. The DSP is pretty easy to work with from what I've read.

You can't change the OPL3 sound on the CS4630 by driver. It's made by the hardware OPL3 clone in the chip; if the clone is bad, there's nothing a driver update can do about it.

Fortunately the CS4630 emulation of OPL3 is done via DSP code which is loaded by its dos driver.

Thanks for raising awareness about these chips it will be fun to play around with them. Never played Half Life for example, and now I've got the perfect excuse to do so 😀

I managed to get a Santa Cruz (Vortex2 A2 also arriving soon), but not tested it yet. I hope it works.
There's also a Hercules Digifire 7.1 (CS4624) within reach. Should I get it? Seems to be the same (bit lower end) design as the CS4630 on the Santa Cruz.

Not overly familiar with the CS4624 other than it's the predecessor to the CS4630.
It seems there is a hoop to jump through to get Sensaura to activate properly in Half-Life, currently testing things out with it and other games under Win98.
I did lots of testing with the Santa Cruz under XP, and it passed with high marks, but never delved into using it on Win98 except for an occasional test here and there.

[edit]Okay got it all sorted, Chaotic WaveTracing is also enabled and working in Half-Life.
It's my first time experiencing Chaotic WaveTracing, it's just like WaveTracing mixed with EAX. Not overly saturated, and very clean sounding. Things reverberate across room boundaries and you can hear super far away.
Really cool! On paper it's stated to be better than WaveTracing, but only more gaming will tell 😉 Some games like Quake3 don't seem to work well with it though, more testing required...

To get it working:
Use the Audio3D.dll 2008 version, replace the Audio3D.dll in windows\system with the ver 4.12.01.2008.
Use the Audio3D.dll 2009 64kb renamed as A3D.dll and also place in the windows\system dir.
For most games stick with using the A3DAPI.dll version 2.25, and if the game needs A3D 3.0 then place the updated A3DAPI.dll into the games directory itself and leave 2.25 alone in the windows\system dir.

Where to get those different audio3d.dll versions?
and as for dosbox compatibility i had in mind the "sound blaster" part, and not OPL3. I have YMF724 installed in my pc for FM midi 😀

Very interesting read! Got a Santa Cruz with the Crystal CS4630-CM EP chip, that I thought was kind of useless for retro purposes. Got it when a friend called to tell me he had found three soundcards that looked really old in a thrift store, and asked if I wanted him to pick any of them up for me. Since they were like $2 each, I just asked him to grab the whole lot for the sake of simplicity. Turned out to be two SB32:s and the Santa Cruz 😀

ZanQuance, how true to the original would you say the A3D 2.0 emulation is in practice? Could the Santa Cruz replace the real thing without any major sacrifices? Wondering if I should keep looking for a A3D 2.0 card to replace the Live! in my main retro rig, or just be happy with the Santa Cruz?

Beginning to look like that sound card haul was a real jackpot 😁

Does the CS4624 chip has the same Sensaura 3D capabilities as CS4630?