The new A3D version 2.0 is a great improvement over its predecessor.  A3D 1.0 was the first 3D audio API developed by Aureal for the PC. This version was adopted by many games and soon caught the attention of sound card manufacturers. Coupled with the Vortex 1 chipset, sound cards were able to produce 3D audio with a standard two speaker or four-speaker configuration.

The final result wasn’t exactly an earth-shattering experience, but it was miles better than the conventional DirectSound3D positional audio. But all of this came at a price, because typical A3D 1.0 acceleration would require something between 20%-30% of CPU utilization, decreasing the frame rate during gameplay. 

Aureal has now changed all this with the second version of A3D.  We received the overview of this version from Aureal’s website.

A3D 2.0 Overview 

Building on the breakthrough success of A3D, Aureal is introducing A3D 2.0 as the next generation of its positional 3D audio standard. Designed to take full advantage of Aureal’s Vortex 2 chip, A3D 2.0 is fully backward-compatible with A3D while introducing the following: 

+ Vortex 2 support: more 3D sources, higher sample rate, bigger HRTF filters 
+ Aureal Wavetracing: real-time acoustic reflection, reverb and occlusion rendering 
+ A2D: host CPU based A3D emulation mode for non-accelerated PCs 
+ A3D API: all-in-one interface to support A2D, A3D, A3D 2.0 and DirectSound3D 
+ Advanced resource management features 
+ A3D authentication protection 

As you can see, A3D 2.0 is completely backward-compatible with the first version, and also supports A2D and DirectSound3D. A2D is an software fallback engine for A3D, used to emulate A3D on systems that don’t include support for 3D hardware decoding. A2D can also be used to "backfill" software rendering buffers if an application runs out of A3D hardware resources. 

The most distinguished feature of A3D 2.0 is the inclusion of wavetracing to simulate realistic environments. By using the wavetracing engine, the sound card is able to produce much more sophisticated audio effects: for instance, to place you in a room and then simulate how sounds would behave when bouncing off of walls or other objects. If you are walking on a metal floor, your footsteps will echo throughout the hallway as they are created by the impact of your feet with the floor and then the sound bounced off the walls. A3D 2.0 also supports a feature called occlusion, the ability to give a sound a blocked property. This will allow sound to be blocked as it travels from room to room or it is blocked out by an object that disturbs the source.  For example if someone or something is standing in front of or behind you, the background effects will tend to fade in volume. Or, a wall or an object could silence gunshots in the next room. Occlusion is demonstrated in the picture to the left, where sound cannot travel directly between the two objects because of the intervening wall. Here, sound is being bounced off the walls (as shown by the green lines) instead of travelling directly (along the path shown by the red line) as in the picture to the right.
 

By using the Aureal Vortex 2 PCI audio accelerator utilizing A3D 2.0, the Monster Sound MX300 is able to calculate the way objects and surfaces in a virtual 3D environment reflect sound, and automatically adjusts the properties of the environment, providing up to 16 3D sounds simultaneously. As a result, sound effects differ from tunnels, caves, walls, open rooms, outdoor environments and battlefields since the reflections and the occlusions depends on the acoustic characteristics of the environment. These simulated 3D audio environments can be experienced from your home PC, through 2 or 4 speakers and headphones.

The Aureal Vortex 2 PCI audio accelerator completes all these tasks without being a heavy burden on the host CPU. This chip itself includes 3.3 million transistors and boasts a maximum audio processing power of 600MIPS. Unlike the previous Vortex 1 chipset, the Vortex 2 features the necessary processing power to take advantage of the newly implemented audio APIs and produce surround sound without eating up valuable CPU cycles. This, in return, provides faster frame rates and places you in the most thrilling and all-encompassing gaming environment possible.