pietcux
Headphoneus Supremus
The Xonar U1 also can do it.
Someone should start a database for these things. Devices that do virtual surround through spdif, devices that do it through RCA, and those that can only do it through the headphone out.
No, you need a soundcard that ALLOWS you bypass it. By chance these xonars do that. You can't just buy any soundcard and expect it to do that. Prior tk me pointing it out, I don't remember seeing anyone mentioning any soundcard doing that.
I can safely say that X-Fi cards can pass CMSS-3D Headphone through any desired output.
Creative said on their website that their sound blaster Z+ cards all support ASIO. I'm not sure exactly if that would bypass the card's DSP as well as the AMP/DAC
What we're looking into here is whether or not a sound card will output headphone-mixed audio over S/PDIF. (Possibly over HDMI in the cases of the Auzentech X-Fi HomeTheater HD and the Xonar HDAV.)