I remember that Roger Waters CD sounding excellent, but on the whole QSound is a bit gimmicky for my tastes and occasionally sounds flat-out wrong to my ears (see Madonna's "Immaculate Collection").
On earlier (pre-90's) Roger Waters tracks you're probably hearing holophonic imaging, which is a variation on binaural recording.
http://en.wikipedia.org/wiki/Holophonics
On earlier (pre-90's) Roger Waters tracks you're probably hearing holophonic imaging, which is a variation on binaural recording.
http://en.wikipedia.org/wiki/Holophonics