To be perfectly honest, I found the Audyssey DSX demo system sounded better than some surround (and high-end stereo) systems I’ve heard in terms of holistic, holographic imaging, but not by nearly as large a margin as some of my fellow editors seemed to experience. I suspect this may have to do with two factors.
First, I’m used to hearing some very high-end stereo systems that offer strikingly good resolution, focus, and pinpoint imaging, and that produce extremely wide and deep soundstages. What those stereo systems may give up relative to DSX in terms of producing an all-encompassing “dome of sound” is offset by their almost eerie clarity, imaging precision, and giant soundstages (albeit with no true surround information coming from behind listening position).
Second, I’m very particular about the imaging of my surround sound systems and am used to tweaking them painstakingly until I not only hear a good, coherent front soundstage, but one that also wraps smoothly to the sides of the room. Granted, I sometimes achieve these results by deliberately positioning my front main speakers somewhat more widely angled toward the sides of the listening space than is theoretically correct. (In theory, the front mains should be positioned roughly 30 degrees to the left and right of the centerline of the system, though I’ve been known to position my main speakers at wider angles than that.). But here’s my thought: I’d rather go with a set-up that is a bit wrong in theory yet that sounds right, as opposed to putting up with the opposite situation (i.e., a system that is theoretically correct, but sounds wrong—yuck!).
At the end of the day, I suspect that the Audyssey DSX system may provide a more reliable and foolproof means of achieving the kind of immersive and holographic surround sound environment we all crave.
At the same time, I think you can get many—though perhaps not all—of the core benefits of DSX technology by carefully setting up either 5.1-channel or even 2-channel systems, using high quality components and paying very close attention to speaker placement (not to mention judicious use of acoustic treatments).
It perhaps goes without saying that one of the inevitable caveats of setting up a DSX system is complexity. In full-blown configurations, DSX systems require nine (or even 11) speakers, not including subs, which—I suspect—is more than many home owners will want to accommodate (except in full-on, dedicated home theater rooms). Even then, properly positioned height channel speakers may pose a problem in that they may need to be mounted near the ceilings—if not in the ceilings of some rooms. It may be, though, that some accessory-makers will devise tall, attractive stands (perhaps with height-adjustable poles?) for use with height channel speakers, assuming the DSX concept catches on.
An open question is whether or not the DSX system is "sweet spot-centric." I don't know the answer to this question, but it arose in a private talk I had with Tomlinson Holman after hearing the DSX demo in the Audyssey listening room. I had the sense that I had experienced most but perhaps not quite all of the benefits of DSX and I asked Holman about the matter. He asked me, "Were you sitting in one of the center seats?" I replied that I had been seated one chair off from the center position. "Then you should try it from the center," he said. Unfortunately, a glitch in the room's media server prevented us from re-trying the demo, but Holman's comment left me with an open-ended question.
Normally, Audyssey’s MultEQ room/speaker EQ system (which I greatly admire) is all about broadening the sweet spot, so that almost every seat in the room becomes a viable listening position. Wouldn’t it be odd if the DSX system, in sharp contrast to Audyssey’s MultEQ system, made systems more finicky in terms of requiring listeners to sit in the “sweet spot?” Only time (and further listening sessions) will provide answers to this one.