Inscrutable, surely you CAN have them spread out too much. Like i said, a lot of how they need to be set-up has to do with the size of the speakers, their dispersion pattern and the listening distance. It's the same thing that we run into for 2 channel use. You have to adjust them according to each individual situation design and the room acoustics.
As to having a center to anchor the dialogue for those not sitting in the sweetspot, that comes back to room dimensions and speaker dispersion. If the room is narrow and the speakers have wide dispersion, you would run into a problem with "overlap" between the three channels. Not only does this hurt overall performance, but the imaging is now blurred and channel seperation less distinct.
In a situation like that ( narrow room ), i would probably forego a center and just use good sized mains. One could even have the tv audio turned on at low level just to center the soundstage somewhat while the mains would do the majority of volume and side to side effects. Like anything else, it's a balancing act. Sean
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