Just get a good pair of Stereo Headphones. Games that support binaural sound (AKA Headphone mode) Do this already in the game. For games that don't support it you can use Razer Surround for free. Does the same thing. You mind can not tell. If you really want some thing with more drivers I seem to remember Tritton had 5.1 head sets in that price range.
If you would like to know more about PC audio and audio myths this site did a few videos a while back.
https://www.youtube.com/watch?v=d1rXcJuEsy0
And here is some more info on Audiophile myths as well.
https://www.youtube.com/watch?v=bjTxEwlypA0
Don't know where part 2 went. Never came out.
Here is a sample of Binaural audio. Use your head phones for this one.