alright noobcakes. this is the awnser:
sound quality is defined as fidelity.
http://en.wikipedia.org/wiki/Fidelity
fidelity is solely based on the idea that the original recording (after it is mixed ect,) is reproduced as close as possible when it is reproduced on another stereo. this means, however the mixer or recording was made - meaning instruments on the sound stage ect, should be exactly as it was done when it was created.
things are currently done mostly digitally with something like protools or the equivalent. one should be able to place the stereo in a anechoic chamber and record the music and be able to directly compare the recording to the original recording with almost no difference.
this is sound quality. the accurate and precise reproduction of the original recording. this is fact, there is no opinion on this.
as far as imaging and stage height, it should take common sense to realize that the recording was made with stereo panning and instrument placement. this should also inherently be recreated just because the play back is identical to the recording. as far as stage height goes - it is also common sense that we stand in front of a musician as music is played. ive never seen anyone who faces the same direction as the musician. so that is common sense as well.
none of this is subjective. none of this is something anyone is required to do. but this is not an argument. it is fact, sound quality is a high fidelity play back of the original recording, regardless of how the recording was made or who made it or what they wanted it to sound like... obviously they made it sound good or you would not be listening to it and that is the point, MUSIC is subjective. what you enjoy listening to is YOUR opinion, but sound quality is not your opinion. this is a totally different subject.