[Tholzel]

Has a practical way ever been found to take 2-channel stereo signal in and result in three channels out, i.e., a true center channel synthesis along with left and right channels that have the mono portion removed?

[Glenn S]

Isn't that what Dolby IIX supposedly does? Able to create all 7 channels from a stereo source.

http://www.dolby.com/resources/tech_library/index.cfm

[mdubrow]

Or Logic 7 from HK.

[Tholzel]

It's hard to tell what you actually get from these various systems, and sure, they all sound pretty good.  But my question is specifically: is it possible to take 2-channel stereo, extract the center channel information (mono) and play it through a (new) center speaker, and then subtract that mono from the left and right channels--and only play "pure" left and right information from them?

[Herb]

It's hard to tell what you actually get from these various systems, and sure, they all sound pretty good.  But my question is specifically: is it possible to take 2-channel stereo, extract the center channel information (mono) and play it through a (new) center speaker, and then subtract that mono from the left and right channels--and only play "pure" left and right information from them?

As others have said, that is exactly what the various processing methods do. With the Dolby IIx you can actually play with a setting that yields wider or more focused front stage.

[rupthekid]

Yes.  Mr James Bongiorno of Ampzilla fame has the SST Trinaural processor that does exactly this.  I believe this room won best of show at CES some time back.  SST also manufactures the Ampzilla products.  Excellent stuff...strange aesthetics.  Never heard the product personally, but they love it overseas in the far east and Japan.