yup. once the sound starts changing with the head movements, the brain will stop questioning if it really comes from speakers. in fact every little thing counts, it's a game of reverse bias ^_^. for example I feel like the sound is much more convincing when I'm listening to headphones in front of my actual speakers, and from time to time I end up wondering if the speakers are ON. something that almost never happens to me when I don't have the pair of speakers in front of me. head tracking is that one little extra thing that may let your brain relax thinking that everything is fine. the game isn't to have the "real sound" whatever that is, but to have the brain stop getting too many contradicting cues. I have the NX head tracker but it doesn't work with win7 because it uses the bluetooth LE thing. so it's pretty useless to me(BTW FU windows, my computer was laggy and 30degrees hotter because I refused to install one unclear update package!!!!!! please force me to install the telemetry thingy in an even more obvious way...). *deep breath* so I can only use it on my portable android stuff with the app that still enjoys crashing from time to time. it's not a global rooted sound path like it is on the basic computer software(the studio mix thing is a VST, not a virtual device), so no movies with head tracking on the train for me :'(. anyway if you have a nice webcam and a lot of light, you can demo the NX softwares on you computer with the headtracking done by the webcam, and see how you feel about it. the settings with the wave NX guys is limited to entering the size of your head and the distance between your ears going around the back. that is used for a default head model that works well for me as a crossfeed setting. but while close enough and maybe better than a few random default crossfeed settings, it's not based on our own HRTF. on the other hand the Realiser(way more expensive and demanding if you want to set it right), will actually measure the sounds coming from your real speakers and then from your headphone with mics in your ears. so of course the result will be much closer to what it should be. the mics aren't positioned at your eardrums but it's probably one of the closest thing you can hope to get when it comes to individual customization and convincing panning. or of course you can try plenty of crossover solutions with plenty of settings and find one that seems to work fine. I've spent years being very satisfied with xnor's crossfeed. not perfectly satisfied, but satisfied enough to almost never listen to headphones without it(I even convert some music in foobar including it for my DAPs).