Say if I were to buy a nice set of headphones such as the HD595's which are known for great soundstaging, what sort of drivers, sound cards, etc. would I have to use to have accurate positional audio. Would I realy have to sacrifice Stereo music quality by buying an X-fi(EAX3,4,5/SMSS 3d), or could I use a good Stereo card such as the Revo, and use DDL, or Direct audio, for accurate positional audio