The Aureal A2D drivers allow 3D Sound on other sound cards, the A2D drivers provide: […]
The Aureal A2D drivers allow 3D Sound on other sound cards, the A2D drivers provide:
DirectSound3D & occlusions support on any sound card with DirectSound3D support
Basic software 3D sound and occlusions support on any sound card without DirectSound3D support.
DirectSound provides the base API and engine, and A3D 1.0 is simply an extension to it to provide added functionality. A3D 1.0 has a similar relationship to DirectSound3D as EAX has to DirectSound3D: it's an extension of the DirectSound3D functionality.
Things are completely different. While A3D 2.0 is a complete sound engine (or simply an added feature) that does not require another API or engine to operate, and is designed to be cross-platform portable, it still sends DirectSound3D calls to the hardware in the cases where it is optimal. These cases exist when the user does not have an Aureal sound card but has another hardware accelerated DirectSound3D PCI sound card under Windows.
While the programmer only has to write to one API, the user still gets the best possible experience according to his or her sound card's capabilities.
A3D 2.0 in this case also augments the DirectSound3D support with the addition of Aureal Wavetracing-based occlusions (the effect upon sounds as they are absorbed and blocked by objects and walls), advanced resource management and improved acoustic effects.
On Aureal Vortex 2 hardware all the features of A3D 2.0 are turned on and run optimally, but in the absence of such hardware, improved audio performance, 3D positioning and other features are still provided to the best of the abilities of the sound card.
So, while A3D 2.0 doesn't require DirectSound3D it's as if the programmer coded to DirectSound3D (with the added bonus of A3D's additional features).