The sennheiser HD-580's were available with a Pro Logic decoder/amplifer unit for a while, but not 5.1. Really though, for headphones, there's no point in having more than one driver because there is no space over your ear to reflect sound and whatnot. Therefore you're left with only processing to simulate the equalization differences or reverb that you would expect each channel to have. Putting more drivers in will do nothing without processing to go with it, and if you're relying completely on processing to begin with, the drivers have no point at all. They're just snake oil for your ears. But like everyone's said, unless this is for gaming where you don't care about sound quality and only about the surround-ness, then just get some stereo headphones.