I built this subwoofer from 3/4" MDF when I was in college and had access to a great wood shop. It was built precisely to a design I bought here - Decware's "The Wicked One": Insane high performance subwoofer. This was the second time I built a sub to this design and this one turned out even better than the first.  It is 48"x48"x13".

When I first tested it, the RA ran over to my room, eyes wide, because he thought we had an earthquake. This thing can hit. And the frequency response curve is beautiful - it sounds good up to much higher frequencies than you'd expect. It has two 10" JBL 4-ohm drivers which you can connect in series or parallel. It does not have a built in amp. The top is 5/8" acrylic. The screws are screwed into inset pine dowel so that the top may be removed and reinstalled. The top is sealed with foam and cork. It's a beast. It's my baby. But, after many years, my wife has won the battle and it's got to go. I hope it can go to a good home.

I'm in Alameda, CA.  Prefer you pick it up; if not please explain how you'd handle shipping.

Photos available upon request - as a new member, I can't add them to the post directly.