Thanks to digital-rights-management issues, some types of surround sound can be routed to your A/V receiver only in the analog domain. And surround-sound game audio (uncompressed PCM) can’t be sent to your A/V receiver at all unless the receiver has six discrete analog inputs.
The game-audio issue is an understandable matter of limited bandwidth, but if your computer has a digital-audio output and your A/V receiver has a digital-audio input, you should be able connect the two using a simple cable.
But in an effort to foil intellectual-property pirates, publishers will only allow DVD-Audio, Super Audio CD, and some purchased MP3 content to be carried outside the playback device only in the analog domain.
Most people don’t realize these limitations until they set about integrating a computer into their home theater—and this is the DTS-610’s raison d’Ãªtre. The device provides three 1/8-inch analog stereo inputs that match the analog outputs on a surround-sound soundcard. Incoming audio is digitized and encoded in 5.1-channel surround sound using the DTS codec, and then output to your choice of optical or coaxial SPDIF. The box also features a digital pass-through: It accepts a digital stream at its coax input and routes the stream to its optical output—and vice versa.
The DTS-610 doesn’t require anything of the host PC, so we didn’t see any performance hit. Even better, we tested the DTS-610 with a Creative Labs X-Fi soundcard and Logitech’s Z-5500 Digital speaker system and were unable to detect any difference in quality between that card’s decoded analog audio and the freshly encoded digital audio emerging from the DTS-610. The less-than-50ms latency was equally undetectable.
The DTS-610 does a great job of filling a very narrow niche: It’s just the ticket for folks who want to integrate a PC into their home-theater system in which analog surround-sound inputs are either missing or already occupied. Other than that, it’s just not very interesting.