ExtremeTech has a nice article on Creative's new Audio Architecture, X-Fi.
About sixteen years ago, Creative Labs gave the PC its voice with the original Sound Blaster, which had an 11-voice FM synthesizer with text-to-speech capabilities, a MIDI/Gameport, and 8-bit mono fidelity. The discrete PC consumer audio market has since expanded and contracted, and Creative turns out to be the first and last man standing. Companies like Turtle Beach have scant presence in the sound card market today, and while newcomers like M-Audio using Via's Envy 24 audio controller have made things somewhat interesting, they don't really pose a serious challenge.
There's been quite a bit of buzz surrounding Intel's HD Audio specification, which debuted with the 925/915 (Alderwood/Grantsdale) chipsets, and for baseline audio functionality, these solutions can be adequate. Some even have S/PDIF output so PC audio stays in the digital domain, and doesn't pick up noise from the motherboard. But for serious audio enthusiasts or home studio engineers, a dedicated sound card is the only way to go.
Creative's "EMU10K2.5" architecture that powers current-generation Audigy 2 ZS cards is a derivative of the original EMU10K1 audio processor found on the Sound Blaster Live, which debuted seven years ago. That's a long time to go between major architectural overhauls, but Creative is the only company left doing hardware audio acceleration. Even so, the company is pressing ahead with an aggressive new architecture called X-Fi, with which the company intends to deliver "Xtreme Fidelity." The X-Fi is poised to bring huge tracts of audio processing horsepower to the PC, delivering new levels of audio effects in games, and enabling very versatile digital audio workstations. Today, we'll take you through the inner workings of this new audio powerhouse, and show you how X-Fi could well reshape the PC audio landscape.