It's built on EAX though. Creative created EAX and then sued Aureal that had created a GOOD solution for binaural wavetracing in games, with a great SDK that made it easy for games to implement it*, in the late 90's. Aureal popped up to be a real competitor like 3Dfx took the world by storm or like how Nvidia just crushed 3Dfx. Creative would have none of that, competition is bad, so they started a bullshit lawsuit against a small company saying they were violating their patents.
Aureal won but it was a pyrrhic victory, it took all their time and money to defend themselves and even though Creative had to pay the court costs they had nothing going anymore. Their only option was to be bought by Creative and shut down, so EAX reverb could plague the ears and shitty drivers could crash computers all over the world.
Fuck Creative and EAX. They're the soundcard creator that killed sound. edit: I'm still salty about that.
* the SDK included material tagging, a texture/surface material could be tagged with their properties like wood, moss, metal etc so there was no hassle to get it going, it had pretty good support for the hot minute it existed and it was awesome.