I've started to work on Master Set with the Orions (these are not really heavy though) and--although I have only had time to do a "pretty good" job setting the first speaker and the second speaker was set even more approximately--the results are really quite good (much more clarity and sparkle, more and better defined bass).
The original location was set in agreement with SL's recommendation that the Orions be at least 4' away from the rear wall and positions were fine-tuned using the out-of-phase tracks on the XLO-Reference Recordings CD and following their directions. I was happy with that set.
Following Master Set through once (with Steve's counsel and advice), and then going back to tweak it a bit (total time maybe 90 minutes), my speakers are now ~ 15 inches closer to the rear wall (and to my eyes, too damn far into the corner and way too close to the lovely "entertainment center" that the love of my life wanted to buy a few years ago). So how do they sound? In total disregard for The Teachings of The Great Audiophiles they sound much, much better and I would be willing to bet that more work will lead to even better results.
I did a little arithmetic: In Master Set you move the speakers 2-3 mm at a time. It's interesting that the wavelength of 12kHz sound is ~ 2.7mm (and 20kHz is around 1.7mm). Further, folks say that when you get Master Set exactly right, the sound comes together in an incredibly satisfying way (I have not yet reached that wonderful state). Briefly, I'm starting to think that it might be possible using Master Set to get speakers set in a room so that they that are effectively aligned within one wavelength at 12kHz (in a way that takes room interactions into account, all this without instruments!).
If you consider the Left and Right sound fields from conventionally located speakers, there will be a central zone (where high intensity L and R sound fields "mix" and interact strongly) with phase cancellations and reinforcements that were not present in the original performance and--to the degree that they are audible--would contribute a degree of distortion. If, e.g., using Master Set, it is possible to get the L&R speakers aligned so that their phases are optimally correct (i.e., as good as one can do with given speakers in a given room) then in the central region where L & R sound fields mix, we might expect a lot less artifactual phase cancellation and reinforcement) and this setup might sound really, really good.
I realize that this may be a controversial idea and that I am not a qualified accoustic engineer (although I do think a lot about wave mechanics for work, it's in a different field). This suggestion is certainly "too simple" and I have almost certainly offended whole swaths of the enlightened, but I would hope that no one get too excited and spend too much time writing long rebuttals. I do have time to read short rebuttals, and might even respond. For the most part though, I will spend my time working on Master Set, listening to music, and tweaking my GK-1. I hope that in taking the time to lay out this idea, I might encourage a few more folks to follow Steve's lead and try Master Set.
Good luck, and may there be the most awesome music in your house,
Peter
