This latest addition to the EAX® family delivers a number of new features that will drive gaming audio to a new level. It delivers double the voice count, so you get more detail and speed in your games. Developers can also add interactive music to games. EAX® ADVANCED HD 5.0 also adds a dedicated bass feed for each of the 128 voices, so gaming audio becomes more cinematic. Next you get Environment FlexiFX, which gives developers total freedom to use any of four simultaneous effects with any of the 128 voices. Finally EAX® MacroFX allows EAX® ADVANCED HD to simulate sounds passing very close to you!
News source: SoundBlaster X-Fi Homepage