The only caveat I would mention is that there was, at least during my first Tri-Center listening session, some shift in overall system tonal balance when the Tri-Center array was brought into play. I discussed this with Diller, indicating that I felt the balance shift was somewhat clouding my impressions of the benefits of the Tri-Center array. Diller replied that he had some Tri-Center tuning and set up ideas that might solve the problem and asked if I could return to Magnepan for a second listening session a day or two later. Since my flight scheduling allowed this, I quickly agreed and found that, on the second visit, Diller had successfully dialed in the system to a point where balance shifts between the pure stereo Maggie system and the Tri-Center system were very small, thus making the benefits of the Tri-Center even easier to appreciate than they had been before
The Tri-Center system, as shown at White Bear Lake, was powered by a very high-quality multichannel preamp/surround processor and a bank of beefy power amplifiers, all sourced from Bryston. When the system is played in conventional stereo mode, the Bryston pre/pro passes unprocessed stereo signals to the power amps and music happens. When the Tri-Center array is engaged, however, the Bryston’s surround sound processing circuits are brought into play. Incoming stereo signals are digitized (if they are not already in digital format) and routed through the Bryston’s Dolby ProLogic II processor, which uses a very specific set of Tri-Center configuration settings. The processor also manages time delay and bass management settings as necessary for the Tri-Center array (technically speaking, the Tri-Center is a “small” speaker, so the processor re-directs bass from the center channels to the left/right main speakers). The Dolby ProLogic II decoder creates the left, center, and right channels signals fed to the amplifiers and on through to the left/right 3.7 speakers and to the Tri-Center array. No rear or surround channels are used at all.
Among audiophile purists, conventional wisdom would hold that less is more, that simpler signal paths always sound better than complex ones, and that two good channels will beat three channels plus a (gasp, choke, gag!) surround-sound processor—especially one with a comparatively humble Dolby ProLogic II decoder engaged. Now ordinarily, I would side with the purists on this point, but the simple fact is that conventional wisdom is wrong in this case. The Magnepan stereo rig as augmented with the Tri-Center array produced a sound that is arguably superior to the results achieved by traditional Magnepan 2-channel system (an extremely good system, by the way)—and without sacrificing any of the sonic qualities purists care about most. In fact, if anything, the Tri-Center array actually enhances some of those qualities, though never in an exaggerated way that would undercut musical realism.
Diller concedes that the Tri-Center concept may be too unorthodox to find widespread acceptance and that it probably won’t help Magnepan sell more loudspeakers, but his position is “it’s an idea that simply sounds so good that we just can’t keep it under wraps.” I’ll second that assessment and offer this bit of encouragement: if Magnepan ever brings the Tri-Center array to a trade show near you, do make a point of going to hear the system. At the very least, it should make one heckuva great conversation starter.
By the way, in case you are wondering, Magnepan is not the only company experimenting with something like the Tri-Center array. At the recent CEDIA 2011 show I had a chance to speak with none other than Richard Vandersteen about the idea of using three-channel systems to listen to stereo material. He explained that he, too, has done considerable research in this area, although his implementation of an appropriate audiophile-grade center-channel speaker is—as you might expect—quite different from Magnepan’s. Vandersteen told me that he often uses a three-channel configuration for his personal home music system, and that it can and does give impressive and musically satisfying results. Interesting, don't you think?