The ability to hear depth within a stereo image is one of the truly groovy, addictive aspects of high-end audio. To experience it, though, (1) your system needs to be a pretty good one, (2) your speakers need to be symmetrically placed within your listening room, and (3) you yourself need to be the third point in a symmetrically consistent triangle with the speakers being the other two. The recording itself.needs to have been recorded much the same way...though it might be said that modern electronic trickery can also go a long way in creating the illusion.
3-Dimensional Soundstage
I have appreciated a quite nice separation of instruments in my system's soundstage. I have read many times about people experiencing depth in their music and have never appreciated this. I was talking to an audiophile friend this week about it and he brought up the fact that recorded music is a mix of tracks and how could there be any natural depth in this? If there was a live recording then yes, it is understandable, but from all studio music that is engineered and mixed, where would we get depth? Are the engineers incorporating delays to create depth?