Asus' lineup of Xonar audio products has been confined predominantly to PCI and PCI Express sound cards. The firm is slowly expanding its selection of USB offerings, though. The latest to join the family is the Xonar U7, which connects via USB and supports 24-bit/192kHz audio.
Asus says Cirrus Logic's CS4398 DAC handles digital-to-analog conversions for the new Xonar. The DAC is a two-channel unit, and the product announcement offers no indication of whether that DAC reserved for the front channel or employed multiple times to cover all eight of the Xonar's output channels. A headphone amp is also integrated, although the part number isn't provided in Asus' press release. The release does, however, indicate that the Xonar U7 has a signal-to-noise rating of 114 dB. That's pretty good considering one of our favorite sound cards, the Xonar DSX, has a 107-dB SNR.
The Xonar U7 supports Dolby Home Theater v4, which includes provisions for surround-sound virtualization and multichannel Dolby Digital output, among other features. There are output options for both analog and digital devices, too. Old-school RCA connectors are used for the front channel output, while 3.5-mm jacks cover the side, center, rear, and headphone outs along with the line input. A digital S/PDIF output is provided, as well.
Unfortunately, Asus doesn't list the Xonar U7's dimensions, saying only that the device is "compact." It looks reasonably small to me, although notebook users may balk at any extra bulk. At least an auxiliary power adapter isn't required; the Xonar U7 runs on USB power alone.
Pricing and availability will "vary by market and location," according to the press release, and we've inquired about what that means for the U.S. I'd expect the U7 to be positioned between Asus' existing USB audio devices. The Xonar U3 is currently selling for $43, while the more exotic Essence One rings in at nearly $600. Let's hope the U7's price is much closer to the former than the latter. Asus' Xonar products tend to sound pretty good, and USB audio devices have definite appeal for notebooks, all-in-ones, and small-factor rigs.