If anyone is looking for a "Super Subwoofer" I would strongly suggest you look into this company, the products represent a real value to performance ratio in my opinion. I recently took delivery of a pair of Deep Sea Sound Mariana 18's and couldn't be happier. Each 18 inch subwoofer has a huge 90 pound magnet/motor with a 4000 watt Speaker Power amplifier. The owner, David Gage, is truly hands on and offered me customer service that was above and beyond reproach (he hand delivered my subwoofers to my home in Naples Florida from Tennessee!). Communication was stellar, sub and amp warranty of five years is tremendous, and an owner who will give you his cell phone number (which he answers) if you run into any set up/performance issues. The bass is effortless, not boomy, and the performance is simply mindboggling. My movie watching experiences have been taken to a whole new visceral level. I never realized how much content I was missing with my 19 year old Miller & Kriesel MX200. I know there are many great subwoofer companies out there with great products but I was specifically looking for sealed subwoofers NOT vented.
They are not cheap but offer a performance per dollar that is tough to beat.
www.deepseasound.com