3 channel the old fashion way in 2-Channel Home Audio Posted January 1, 2016 I did this a few years back. Rolls makes a small mixer that works like PWK's circuit and mixes stereo to mono. Just add an amp and you get a summed mono center. Had a La Scala between two widely spaced K-horns and this setup worked well. A modern ht receiver will do it easier and better though. So I would be wasting my time, is that the general consensus of others who tried it as well?