BTW, one last thing: don't use a single surround back speaker if you can avoid it. Psychoacoustic studies have shown that sounds along the centre line can be confused; i.e., with a single back speaker, sounds from behind can sound like they're coming from in front of you.
Somehow I get the feeling, that ancient man, never confused the growl of a saber tooth tiger from *behind* him to *in front of* him.
Especially with the video cues coming from your display.
