It's been almost a month since I received my M20's and B15, so I thought I would give you a review of what I'm hearing so far. I'll also add some comments about the PSB Alpha Intros that I'm now using as my Center and Rear speakers. You may remember that I originally used the 80Hz crossover in my Marantz SR-18. The following comments do NOT refer to that connection option. The SR-18 sounds best in Direct mode, which bypasses all internal crossovers and tone controls. The only thing the SR-18 does is D/A conversion (it's D/A's are superior to the old Sony ES CD player I use as a transport) and amplification. I have y-connectors on the pre-amp outputs, one set returning to the main-in for the left and right channels, and the extra set driving the B15 through left and right line-level connection. The B15's low pass is set at 80Hz, 24dB/octave. Using the Low Frequency Optimizer test disc and computer software, I measured the sub's output from 20Hz to 100Hz. The measurements from your Radio Shack sound meter are input on your home computer and the software corrects your readings for measurement errors, and then spits out a picture of the sub's control panel with the recommended settings for the B15's built-in equalizer. All very easy, and very cool. Once this is done, you should have the flattest response that the sub is capable of in THAT position. Revel does recommend that you re-do the testing from several different positions to find the best one. I only have one spot for a sub, so I only did the measurements once. Although I plan on recalibrating in a month or so when the sub is fully broken in. Now, on to the sound. I have never heard better sound in my system. Period. The M20's are VERY revealing. In fact, I can imagine some people might find them too revealing. Personally, I was looking for a very analytical speaker. I can hear the saliva in singers' mouths, I can hear cord changes on acoustic guitar, I can hear piano pedals, I can hear Ray Brown mumbling along as he plucks his Bass... you hear EVERYTHING in a recording... I have the M20's toed-in to point directly at me, and yet the soundstage extends well to the sides, beyond the boundaries of the speakers. The imaging is very precise. Both laterally, and depth-wise. I've never heard the front to back placement of instruments to this extent before. When listening to Coldplay's Parachutes, the acoustic guitar on track 6 was left of center, and hanging in the air in front of the lead singer's voice... even in front of the M20's it seemed! Very cool. It's interesting to note that before I hooked the sub up, I was using the M20's on their own, and several people assumed I had the subwoofer on. They are rated for in-room response to 46Hz, and it feels even lower. They really could pressurize my small room (10x15) on their own. Of course things are even better with the sub. Now for the B15. I've obviously never heard deep, accurate, musical bass before. I feel like I have a whole new rack of cd's. Radiohead's Karma Police has a kick-ass bass line that my OM-6's obviously were not doing justice to (despite being rated to -3dB at 18Hz, at least on paper...) Kent's Isola (the best rock album of the last 5 years IMHO) has always had incredible bass, but now it doesn't rumble like it did on my OM-6's. What I thought was a rolling synth bassline is now individual notes, or individual sustained bass tones. I never knew I could hear actual notes down that low. Despite the fact that my focus has moved away from HT towards 2-channel, I still enjoy a good DVD. The B15 excels at movies as well. Although again, some scenes that rumbled on my OM-6's now seem to have perceptively LESS bass because they aren't as rumbly... probably because the B15's in-room response is flatter, and the B15 has less distortion. But, when there is supposed to be bass... WOW! This sub definitely hits harder and lower than the OM-6's ever did... and it should, since it retails for more than the pair of Mirages. I am now using a pair of PSB Alpha Intro LR's for my rear channels, and the Intro CLR for my center. My father has been using the same speakers for over a year in his HT, so I was familiar with their sound. I have always been amazed at the rear soundfield these tiny direct radiators produce. I used to joke that my dad's rear soundfield was better than mine at 1/3 the price. (I was formerly using OM-R2's). I am definitely not as critical of movie soundtracks as I am with 2 channel music, but the rear soundfield sounds far more detailed now... and I don't feel like I've given up any spaciousness, despite the loss of bipolar radiation. Also, these tiny speakers play plenty loud in my small room. The Intro CLR is also more than satisfactory. Dialogue is far more intelligible than it was on my OM-C2. While the OM-C2 is the perfect match for the OM-6's, I have always found it to smear dialogue slightly. Is this due to it's omnipolar configuration? Is THX on the right track with it's 'no reflections' limited vertical dispersion theory? I dunno... but dialogue is clearer to me now. Volume again is not a problem... at 9 feet away, this center plays plenty loud. My only criticism would be that the CLR seems a bit shy in the 80-120Hz region, meaning that on it's own, voices don't sound as full as they did on the OM-C2. However, as part of a 5.1 soundfield, I can't say that I've noticed this deficiency... and it certainly hasn't detracted from my enjoyment of movies. For me, this switch in my system from a 'flagship' home theater speaker set (the OM's) to a strange combination of more expensive Mains/Sub and cheaper Center and Rears is exactly what my ears needed. If you want me to elaborate on anything, just ask. Happy Listening, Craig.