That would be DICE's incredible sound engine technology at work my friend, so pretty much any surround virtualization technology is going to work really well - I also have THX Tru Studio on my soundcard. I know you're a huge fan of positional cues so this is probably making you drool haha! If you truly want your mind=blown (if you ever start playing online with people you know that is) check this out: http://mumble.sourceforge.net/Positional-Audio & http://mumble.sourceforge.net/Games This just solidifies the whole experience!
Then why do I find BF:BC2's positioning to be so terrible and inaccurate no matter what combination of audio settings I use between the game itself, Windows, and the X-Fi drivers? The sound samples themselves are good, but it's extremely difficult to figure out where they're coming from, and close analysis of the grenade explosion sound effect revealed a canned stereo pan regardless of what direction the explosion is coming from.
It was a big step back from the Refractor engine titles (BF1942, BF:Vietnam, BF2, BF2142), but those just used DS3D or OpenAL like everything else at the time.
Just not my experience, I guess. Previous iterations, yes. The beta, yes. Those had problems. Not BF3. I've been a pretty competitive FPS gamer for quite a while and what Frostbite pulls off is just really impressive to me. You want horrible positional audio in a competitive FPS? Check out Planetside 2. I love that game, but its audio is so incredible inaccurate.
BTW, Planetside 2 as an exclusive to PS4... that's a reason to be excited about that system. Doesn't matter to me as I'd rather run it on a PC, but if you're trying to be excited about PS4, it's definitely a great reason to be.
Again, I just don't get it, because PlanetSide 2 at least has par for the course software audio mixing. I can tell where sounds are coming from with relative ease. That never happens with BF:BC2.
BF3 may be different, but I'm not holding my breath that they suddenly fixed the audio mixer for Frostbite 2.0. I'll find out soon enough...it's already June 13 here, but the Origin store hasn't updated yet.
Oh, and if PlanetSide 2's going to run on the PS4, then they'd better make sure the framerate doesn't dip below 20 FPS every time you take part in the middle of a really big fight, like at The Crown. The current PC client wants your CPU cycles, all of them, and a 3.0 GHz Q6600 isn't enough. If the forums are any indication, even the latest Ivy Bridge and Haswell i5/i7s at over 4 GHz struggle just as hard. It's arguably more demanding than Crysis.