Would center channel benefit audio only room?


I want sound that will fill my listening room from top to bottom, without replacing existing speakers.
orpheus10
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.
To learn more about the benefits of a 3-channel audio-only setup, check out:

Trinaural website @ Spread Spectrum (Ampzilla2000)

and

The MilesTech website
Refining speaker placement seems like a reasonable place to start before recommending purchasing another speaker and more electronics. It takes only five minutes looking at the Virtual Systems to see that it's not uncommon for speakers to be positioned improperly. More than a few people don't (or can't) position their speakers in a way that will create a correct stereo image.
onhwy61, the room size is 14 X 20, the ceiling is vaulted 8' at it's lowest level. My speakers are 3 way custom utilizing a Heil AMT tweeter. The soundstage is 3D left to right all the way across the room, but it is only 4ft tall.