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A3D 1.0 was only a basic software HRTF implementation with some distance filtering, AU8820 Vortex 1 ASIC's do no have any hardware HRTF to accelerate A3D 1.0. Every other card that offers A3D 1.0 should be using the same algorithms Aureal licensed out at the time and should sound about the same depending on how they decided to utilize their own DSPs.
The AU8830 Vortex 2 ASIC has hardware FIR filters for accelerating the A3D 1.0 and 2.0 HRTF and should be the optimal representation of A3D.
The EMU10k1 on the Live! is a decent DSP design but doesn't offload A3D 1.0 at all, instead their wrapper converts all A3D 1.0 HRTF to DX5's DS3D.

The S/PDIF support on the Vortex cards is known to have some issues due to driver bugs, so test and see. Where the Vortex will be desired is for the broader non-EMM386 DOS compatibility across more systems, but I hear the Yamaha YMF7x4 chips are a better contender all around and have real OPL3 rather than Aureal's software emulation. Neither the Vortex 1 or 2 have hardware OPl3 in them.

Chips such as the Crystal CS4630 DSP use Sensaura's algorithms for offloading/accelerating A3D 1.0 and some features of A3D 2.0 in their hardware and do a great job on both, but the OPL3 emulation in DOS is seriously flawed.

In general, and this goes as a general rule of thumb now for every user who comes across this post in the future:
Use Creative cards for EAX and MIDI.
Use Aureal Vortex 1 cards only when you cannot get hold of the better Vortex 2 for everything A3D 1.0 related.
Use Aureal Vortex 2 cards for everything A3D related.
Use Sensaura based DSP's like the CS4630 as a Jack of all trades for EAX 2.0, A3D 1 and 2, and really good MIDI support. (BUT NOT FOR DOS!)
Use original ISA hardware or Yamaha's YMF7x4 cards for better OPL3 support in DOS.

Hope this helped.

As for your last point, I'd add that all PCI cards with decent OPL3 implementations and good audio quality are worth looking at for DOS (of which the YMF-PCI family is one of a handful of options), but your best option depends heavily on motherboard compatibility.

Thanks for the advice.

I use this mostly machine for Windows 95/98 gaming and aren't too worried about having perfect DOS sound compatibility. I'll look into ISA cards with real OPL3 if I ever want to add that capability, as all 3 ISA slots on the board are still free.

I don't remember the exact board model off the top of my head, but it's a Slot 1 QDI-made board, with a 700 MHz PIII installed.

From what you're saying, while good single card solutions like the CS4630 exist, I'm not going wrong with keeping the SB Live! Card for EAX support and installing a Vortex 2 card for A3D (my vortex 2 card is already on order).

I'll experiment to see what mileage I get vis-a-vis S/PDIF output. AFAIK HRTF is meant to simulate a 3D effect when using headphones, but I mostly use a discrete 5.1 speaker setup.

As for MIDI support, I have a MIDI breakout cable for my SB live! and a real working condition SC-55. Not sure I can get better quality than that 😉

You already have a pretty ideal setup it sounds, no need to change anything then 😀
A3D works with speakers as well, but Sensaura's 5.1 speaker multidrive HRTF on the CS4630 is pretty awesome as well. The Vortex 2 only does the Crosstalk cancellation on the front 2 speakers and basic panning on the rear in the 2041 and 2048 drivers (Superquad mode) but still sounds just fine.
Quad speakers just expand the sweet spot for center HRTF positioning, 2 speakers is actually all that's required for good HRTF.

Does Vortex 1 work on Windows XP with A3D ?

idk about A3D but the XP drivers are kinda crummy

Only the Win9x drivers are completely functional.

ZanQuance wrote:

Use original ISA hardware or Yamaha's YMF7x4 cards for better OPL3 support in DOS.

I think johnsirett asked nothing about better OPL3. He said about better DOS compatibility. And true OPL is not equal to DOS games compatibility.

For better DOS compatibility there are ISA SB Pro clones - ESS, OPTi, Crystal, AD, YMF718/719. All have good compatibility whatever their FM synth quality.

PARUS wrote on 2019-08-31, 21:24:

ZanQuance wrote:

Use original ISA hardware or Yamaha's YMF7x4 cards for better OPL3 support in DOS.

I think johnsirett asked nothing about better OPL3. He said about better DOS compatibility. And true OPL is not equal to DOS games compatibility.

For better DOS compatibility there are ISA SB Pro clones - ESS, OPTi, Crystal, AD, YMF718/719. All have good compatibility whatever their FM synth quality.

I don't understand what your saying here. I posted that only "IF" good OPL3 support mattered, he didn't need to ask for me to offer a suggestion about it.
I wasn't excluding any of the cards you mentioned...but I disagree that the "Crystal" CS4630 on the Santa Cruz would classify as compatible OPL3 support, it's literally the worst I've ever heard and is unbearable to listen to.
So not all cards are good DOS cards if quality and accuracy matter to you.

A CS4624/30 + an ISA card with good FM Synthesis is my favorite Win9x/2K setup as of late but I can live with an Aureal + ISA setup as well if Win2K can be omitted.

For non-ISA setups my favorite PCI solutions as an FM Synthesis card are ESS Solo-1, Fortemedia FM801, Yamaha YMF744 or Azfin AZF3328 - they all sound good to great, but compatibility varies depending on host PC.

I used to use Aureal cards for FM and thoughr they sounded good. I was wrong, they sound barely passable in that regard. Phil fooled us all 😁