Reflected sound is therefore essential in 2-channel audio to create the proper imaging of stereo. Unfortunately for me I have never heard 2-channel sound better than MC. But I know now it's because the room is the essential factor in creating the illusion and it's just as important as the speakers.
I think what your experience is really telling you is that more than two channels are essential for creating the illusion rather than two channel plus a lot of room reflections.
For example when you say "I could hear the plane behind me almost as equally clear as in front as the sound reflected off the brick building behind me," is that what you
really want to hear from your audio system? Do you really want it to sound like the band or orchestra is simultaneously both behind and in front of you?
The likely reason you have never heard two channel sound better than multichannel is because multichannel attempts to capture (or at least synthesize) the ambience of the environment the music was created in. When you're at a live event, what you hear other than the direct sound coming from the instruments is a result of the acoustics of the venue where the event is taking place.
If you rely on two channels plus the reflections created in your listening room, then the acoustics will be that of your listening room. I don't think you'd care much for the sound of a symphony orchestra actually playing in your listening room.
I think two channel audio should simply be accepted for what it is and what it was intended to be, limitations and all. If you want to go beyond that, multichannel is the way to go.
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