A left/right/center blend is a classic loudspeaker setup. Many of the great Mercury recordings of the 50s were recorded in 3 channel stereo. In the 60s Dynaco had preamps that would process 2 channel for a pseudo 3 channel effect. Currently, I believe the Meridian processors have a tri-field process. About a decade ago I heard a demo that was quite good. I'm not sure why people are dismissing this out of hand. It's not to be confused with home theater.
To the OP - this is not your first post on this subject. As far as I can tell you are refusing to give relevant info about your current system and room. People have asked and you do not provide. It really hinders the ability of anyone to help you.
