BGX-4850, so we were pretty happy to see that AVGuide put them to a review. Word to the wise -- don't scoff at the small 4-inch drivers used in this subwoofer; by packing 48 of those little cones into each module in a kind of boxer style layout (Porsche and Subaru fans take note), the BGX-4850 (combined with a 2,200-Watt amp and a healthy dollop of DSP) turned loose sub-20Hz response that the reviewer ate up. No smudgy, slow, plodding bass here -- quite the opposite, actually. The reviewer said the transient response may outpace some of the primary speakers with which it's paired; something good is going on here. Good enough, in fact, to net perfect 10s for everything but the "value" portion of the competition; somehow you just knew that $7,000 tag would catch a snag somewhere along the way.