I have to admit up front that I'm pretty clueless about computers and computer audio. I use a pair of Audioengine A2 speakers hooked up to my Mac Mini, and the combination sounds fine to me. For "serious" listening I have a pair of Magnepan 3.6 speakers hooked up to my hi-fi system on the other side of my loft apartment. Computer audio is a low priority.
But computer audio is coming on strong, even among serious audiophiles. Need proof? Stereophile magazine's editor, John Atkinson, has been using and occasionally reviewing the best-sounding computer audio gear for at least 10 years. Granted, most high-end audio is expensive, so I was pleased to see Atkinson was smitten by a $200 sound card.
The Asus Xonar Essence ST/STX PCI and PCI Express review appeared in the January 2010 issue of the print version of Stereophile and is now on the magazine's Web site.
Sure, you could get computer audio over S/PDIF, USB, FireWire, Wi-Fi, or Ethernet connections, but that's not what the Asus Xonar Essence ST/STX sound cards are for; they plug into your PC's motherboard. Old school, but audiophile quality to be sure. I'm leaving out most of the nuts and bolts computer stuff; read the actual review to get the detailed rundown.
When Atkinson listened to his iTunes library of FLAC and uncompressed AIF or WAV files he found that "low frequencies had suitable impact and weight, the midrange was uncolored, with excellent clarity, and the high frequencies sounded very clean, with good air around sound sources."
Even with Atkinson's own high-resolution 24 bit/96 kHz piano recordings, the sound card shined. He noted that "the Xonar Essence did a great job of conveying the full weight of the Steinway D as pianist Genadi Zagor pounded its left-hand keys at the climax of Mussorgsky's 'Pictures at an Exhibition.'"
Bottom line: the Xonar Essence is a truly affordable way to get bona-fide high-end sound from a computer.