A very necessary evil

There’s no good reason for the existence of Asus’s Xonar HDAV 1.3 Slim soundcard, and yet it’s a godsend for those of us who want to hear the high-definition soundtracks on so many of the Hollywood movies released on Blu-ray disc. Blame Microsoft for the contradiction: No one would need a product like this if Vista provided a protected audio path.

After all, this card doesn’t decode Dolby TrueHD or DTS-HD Master Audio soundtracks, nor does it enhance the audio or the video; it just passes the signals through to your A/V receiver. Using the included HDMI cable, the card takes the output from your videocard, re-encrypts the soundtrack so that no one can intercept the bit stream to make a bit-perfect copy, and outputs the encrypted audio and video to a second HDMI port. For those without HDMI, Asus also includes a DVI-to-HDMI cable.

The protected audio path requires a software component, too, so Asus bundles a copy of ArcSoft’s TotalMedia Theatre with the Xonar. Not your favorite media player? Too bad, it’s the only one that’s compatible. For what it’s worth, we don’t have any complaints about the program. There’s nothing objectionable about its user interface; it can handle all the major codecs; and it supports BD-Live, so you can access whatever online content is linked to the movie you’re watching.

Your home-theater PC will downsample Dolby TrueHD and DTS-HD Master Audio soundtracks unless it provides a protected audio path such as Asus's Xonar HDAV 1.3 cards do.

Asus actually has three cards in its Xonar line that are capable of pulling off this trick. The HDAV 1.3 Slim, however, is the only low-profile card in the lineup, and it’s available only in a PCI formfactor. That’s unfortunate considering that our current favorite home-theater PC platform, AMD’s Live Home Cinema, ditched that aging standard.

So we dragged our desktop rig, which is currently outfitted with an HIS Radeon HD 4770, into our home theater for this evaluation. We connected it to a Yamaha RX-V665 A/V receiver, which is in turn connected to a 42-inch ViewSonic N4285P LCD television. We used Klipsch Reference Series RF-35 loudspeakers. In terms of image quality, the PC clobbered the Samsung BD-P1600 stand-alone Blu-ray player we used for comparison. But the Xonar card doesn’t perform any video processing, so we can’t give it credit for that; more importantly, the PC didn’t sound any better than the Blu-ray player. Then again, the PC would be forced to down-sample the soundtrack without the Xonar card in the loop.

To get lossless Blu-ray audio out of your PC, you'll need to also play the movie using the included ArcSoft TotalMedia Theatre player.

The HDAV 1.3 Slim has a front-panel output header that you can connect to your enclosure’s headphone jack, and a four-pin auxiliary input header you can connect to your TV tuner’s analog audio output. The mounting bracket has an S/PDIF output that can accommodate both coaxial and optical connectors (with an adapter), along with the aforementioned HDMI input and output. The card is compatible with the HDMI 1.3a specification and supports all three of its optional features: Deep Color (up to 48 bits per pixel, compared to HDMI 1.0’s 24-bit color), the xvYCC color space (which means the card uses the full range of values in an 8-bit space), and both lossless audio codecs.

Nonetheless, there’s really only one reason to buy an HDAV 1.3 Slim: So you can enjoy the splendor of Dolby TrueHD and DTS-HD Master Audio soundtracks while taking full advantage of your home-theater PC’s video capabilities.

Asus Xonar HDAV 1.3 Slim

Upscaling

Delivers HD audio from a home-theater PC without downsampling; low-profile design.

Downsampling

There's no PCI Express version; compatible only with ArcSoft's TotalMedia Theatre.

Asus