If you're into organ music or action flicks, this is the sub for you. This sub produces clean, undistorted bass to 17Hz. It is incredibly efficient, at ~95dB with a one-watt input.
A favorite demo of mine is the intro to "Under Siege 2". When the shuttle lifts off, my listening room shakes with such force that you begin to fear for the structural integrity of the house.
I built this from a five-foot by 10-foot sheet of inch-thick MDF, using plans and drivers from VMPS. If you can get this massive sub (it weighs 135 pounds and its internal volume is 8.25 cubic feet) past your wife, you'll enjoy the best bass you've ever heard. And it's a bargain, too. The kit was $329. The MDF was ~$50, and the Birch veneer was ~$100. It's so efficient that it doesn't require a large amp; I use a $300 Marantz 125wpc monoblock. You'll not find better bass for $800.