Chip in with your own pipe dreams and let's hava little fun. Project 1: Wall of sound Step one: Wall off the front third (or about 3000 cubic feet, which ever is greater) of your home theater with multiple layers of MDF, cross-brace it and seal it up. This is your enclosure. Step two: visit Orevox and place an order for enough DS-312 12" drivers to completely encrust your new wall. For example, if your wall is 16x8 ft. you'll snap up 128 of 'em. They're less than 9 bucks each, so quit whining. Sure their T/S params stink, but you're overcoming wimpy wimpy quality with hefty hefty quantity. Step three: Get busy with your router and circle jig, making homes for all 128 little air pumps. Weary not in well-doing. Step four: Mount drivers, wire them series/parallel, and connect them to a modest amp of 250 watts or so, downstream of a LT circuit to flatten the humpiness of the high-Q drivers. Step five: Stand back and survey the damage. For about $1200 in drivers, plus modest outlay for lumber, amp, LT circuit, and assorted sundries, you now have a subwoofer with the following characteristics: A radiating surface equivalent to a single 9 1/2-foot driver that will displace over 2500 cubic inches of air at a mere 1/4" of p-p excursion. (Single-digit Hz? Yes--loudly.) A baseline anechoic efficiency of over 107 dB/W. A theoretical anechoic 131 dB at 250W (at which power level each driver will see just less than 2W.) An eye-popping decor theme!