I can't tell you much about the Auzentech Bravura, but I do have first hand experience with the Asus Xonar D2X, Xonar D1, Creative X-Fi Titanium Fatal1ty, X-Fi XtremeMusic and X-Fi Titanium HD. I've tested all of these using my JVC HA-DX3 headphone and Klipsch ProMedia 2.1 speakers and I'll have to say that sonically, the Xonar D2X and the Titanium HD are the best ones. I can't really say which of the two is better, but the D2X has some nifty features like LEDs on the outputs to help you plug in wires when the computer is on and has a really nice DAC chip as does the Titanium HD. The D2X is also 7.1 capable through analog connections (TRS), something that the Titanium HD is not capable of without connecting it to a receiver that takes optical. In that case, I believe it can only do 5.1, according to the Console Launcher.
Both are very good with music and movies but the D2X is very rich sounding. I know that's a cliche word but it really does come down to that. If used in stereo (2 channels L/R), the D1 and D2X are hard to discern. However, the X-Fi Titanium HD, on the other hand is somewhat different from those two. It sounds "thinner" than the D1 and D2X but not by much but it gives a great sense of space. Those three cards are all very detailed but the Xonars are not as good for gaming sound positioning (particularly FPS like BFBC2), something that the TiHD does extremely well. That's what made me pick the TiHD over those two. I've had my D1 for about 6 months and it's probably going to be given to my parents. It's a nice card, but running around half deaf no matter what setting I choose in the control panel breaks the deal. The D2X is just about the same when it comes to positioning in games.
Edited by RallyMaster - 12/30/10 at 9:46pm