Originally developed in 1997 in collaboration NASA (National Aeronautics and Space Administration) for use in flight simulators, Aureal's A3D technology has subsequently progressed through a number of versions.
ASD1 improved upon DS3D by providing hardware acceleration, a more advanced distance model allowing simulation of different atmospheric environments, such as thick fog or underwater and a resource manager that allows developers to take advantage of the number of 3D streams the sound card can handle and control use of Aureal's 3D sound algorithms.
The A3D2 version actually takes the geometry information of the room that is fed to the graphics card, and uses it to render realistic sonic reflections and occlusions . Using a technology called WaveTracing, A3D2 genuinely calculates up to 60 first-order reflections, which interact in real time with the environment, and then groups later-order reflections into overall reverb.
ASD3 takes the technology to the next level by adding a number of new features:
A3D2 was such a computationally complex system that Aureal developed a processor dedicated to the necessary number crunching. A3D3 requires even greater processing power, which is provided in the shape of an additional DSP to accelerate the new commands.
The fact that AD3 was considered by many to be the technically superior standard proved of little consequence when, after two years of litigation with Creative Technologies, Aureal filed for bankruptcy in April 2000 and was subsequently taken over by its erstwhile rival a few months later.