3 channel stereo music processor

I have 3 identical Tekton S-Lores for my LCR. What is the best (most flexible?) way to process two channel stereo music to originate the center channel signal for listening without the rear surrounds. I know everyone says to listen to two channels. But my set up is strange thanks to my wife's mandatory furniture arrangement. At this point for digital manipulation for a center channel I am using my Marantz receiver. I am considering a Harman Signature Citation 7.0 analogue processor as an improvement. Dose anyone have a comment on this or a alternative that is not crazy expensive?
My H/K Signature 2.0 pre-pro was a very good-sounding unit, $2500 MSRP. I have purchased 2 of these units years ago for approx. $350 ea., used but in terrific condition It seems they are up to around $600 at Amazon right now.

It may be time to dig those bad boys outta the attic and sell 'em...

See my review of the Trinaural processor. Still the best I have heard.

I have run a center channel for about 40 years for reason of room layout (like you). Much of that time I used a center channel derived in the same way as the rear channels in the old Dyna quad setup (bridged across the stereo amp). Except that I inverted the signal for one channel (easy to do with a phono cartridge) so that the bridged signal was L+R (L-(-R)) as desired for center. This produced excellent results and was inexpensive because no extra equipment, not even an amplifier, was necessary. Of course the stereo channel with the inverted signal had to have its speaker wiring inverted to compensate.

Most stereo power amps deliver more power when one channel is inverted. I never had any problem with the low impedance load due to the bridged speaker.
If you are looking to acquire an entire new system from the ground up, Meridian's Trifield technology provides about the best "stereo" sound I have ever heard, from an imaging perspective. I don't know if they still offer this on their new (and expensive) systems, but my old 561 processor had it and it worked great. Must use Meridian "digital" speakers, though (hence the entire new system comment)
+1 on Meridian Trifield...

really increadible experience when the front three channels are well matched. you can pick up one of the older 5 series processors very reasonably now - they sound great in trifield and can be used with any speaker.
See post in the other thread.