ASUS Xonar Essence STX
 

The majority of the high-end PC audio cards targeted at enthusiasts typically focus on multi-channel performance, with a variety of decoding modes, DSP enhancements, and other features tossed in. The Xonar Essence STX from ASUS has an entirely different focus - delivering audiophile-quality stereo output.
http://techgage.com/article/asus_xonar_essence_stx/