Jack, I think you should have stayed in mixing school a bit longer. Typical mixes are of single mono tracks, each panned to a specific point in the L/R spectrum. So a mono (single channel) vocal track panned center, should appear dead center during a stereo playback. It's exactly the same thing as splitting one feed into two channels.
Frank, I don't see the value in your positional test. Up that close to the speakers, the mono presentation should be rather broad left to right since you're not at the focal point of the speakers. As you then move right to left all you would notice is a weakening of the opposite channel, and some phase shift between the two.
The most correct way to judge the center channel, is to imagine a line drawn on axis from the front of each speaker cabinet toward your listening position. Where the line from each speaker intersects is the center channel focus point of the speakers. Whether you're listening to mono or stereo material, if you position your head so the point of the intersection of the lines is right on your ears, and then move your head forward and back relative to the intersect point, you should find a point right behind the point (to the rear) where the center appears to be right in front of you. Move back a little further and the image moves away from you (clearly), but move forward and the point moves behind you, which gives you the effect of being more surrounded by the soundstage. Generally speaking, the ideal listening position is with the point right in front of you, but some like the image submersion you experience by moving forward a bit. The only problem with that is that the center channel information becomes less focused as you move forward.
It's essential to the stereo sound stage reproduction that you can clearly identify this point and move around in front of and behind it. At my seated position at the DAW display monitors, I'm slightly forward of that audio point, but can easily move in and out of it to judge sound stage positioning and placement. It also helps give you a mixing perspective balancing center channel to side channel levels.
--Bill
There's nothing more I can really say Tim except that is in the curriculum of at least three educational recording institutes that I know of, one of which I attended. You keep talkng about mics and how they don't know stuff. Well a chisel doesn't know stuff but that doesn't stop a sculpture from making things with them. You also keep on using your microphone rant in a mono context when we aren't talking about mono. A mono mike won't give you a stable center image unless you split the signal in two and play them back as if there were two of them. You don't need a center channel to get a decently convincing center image out of two spaced loudspeakers so I don't see how you can even say you require a discreet soundsource and a discreet signal to simulate one. On the latter how do you think simulated multichannel center and rear channel signals is created from two channels? Your logic, pun intended, just sucks. So while you and Bill are absolutely correct that there is no height information on the raw mic feed on one track, this little nugget of truth is actually insignificant in the broader scheme of things. Sometime I think you just see no value in the importance of psychoacoustics referenced by Micro, Odin and myself. All from someone who has said after all that the end result that matters. So either you reject the concepts on a narrow dogmatic ground or still can't grasp them.
