I recently put together a new gaming PC and ran into an unanticipated audio conundrum. I have an Astro Mixamp that I used to use with my Xbox 360 primarily to play game with Dolby Headphone (which I fell in love with in Dead Space and Battlefield 3). I thought that I would be able to use the SPDIF out on my motherboard (Asus Z87-Pro) to output 5.1/7.1 to the Mixamp and get Dolby Headphone out of my PC that way. Turns out the Z87-Pro only supports DTS/DTS-Connect and not Dolby Digital Live (required for the Mixamp) so I'm left deciding what the next best decision for my PC Gaming Audio is. The headphones I'll be using are the Audio-Technica ATH-A900X.
1) A soundcard like the Asus Xonar DX supports Dolby Digital Live (encoding). I can definitely use the SPDIF out on the card, feed it into the Astro Mixamp, and have Dolby Headphone into my headphones output that way. Or...
2) The Asus Xonar DX supports Dolby Headphone already. Does this make the Astro Mixamp redundant? Has anyone experienced any difference with DH on a sound card like the Asus Xonar DX vs Astro Mixamp?
3) My motherboard's onboard sound supports DTS Ultra PC II which has virtual surround sound of it's own kind. Does anyone know how DTS Ultra PC II sounds for gaming? (I currently am running a test OS and can't install the drivers yet).
Thanks for your help!