3 channel sound

At Axpona Chicago I heard the comparison of stereo vs. 3 channel (Oscar Peterson and Nat King Cole's selections) through Mytek Sony Pass 5 channel dsd system. I was stunned with the change in focus of the image. Not 5 channel nonsense where music comes from 5 speakers (sorry Dire Straits) just 3 channel.

My question is besides VAS Audio, who offers a 3 channel preamp/processor? Only other one I know of is old H-K that the VAS is based on.

Has anyone ever heard the TriSound processor that James B. had released shortly before his death?
When I first got interested in three channel I didn't find any vendor but VAS. I have the VAS and use it in three channel mode, driving VAS mono blocks. The center is a mix of right and left channels. Sounds great on some media. Remember Paul Klipsh started this innovation back in the 50's when he married corner horns with a center channel belle. The VAS stuff is great sound, great value.
1. I reviewed the Trinaural here: http://www.stereophile.com/musicintheround/904music/index1.html

2. The VAS and the Trinaural derive (synthesize or extract) the center channel from a stereo signal. It is not quite the same as a discrete 3 channel (SACD) signal.
Duh. I actually use Trifield on my 861 but I don't usually suggest Meridian since it is expensive and not mainstream.