Jonno said: And it's otherwise a strong sounding track - impressive bass on the Nostromo landing sequence, particularly in comparison to the 2.0 surround track (which presumably comes from the 35mm stereo mix).

I've never understood how a presumably pure stereo track can become a 2.0 surround track. Where does the matrixed surround sound come from if the source is two channel?

I also don't understand why the other mix on the BD is 4.1 and not 5.1. If it comes from a six-channel mix, why is it not 5.1?