What sub under a grand?

I use Rythmik subs and can absolutely second the recommendation, but I'd also think hard about the SVS dual SB-1000 offer. A pair of sealed SVS subs with 12" drivers at $950 is probably a great way to maximize your chances of getting great sound, because A) SVS makes a very highly regarded product and B) dual subs offer a lot of placement flexibility (which really improves your chances of smooth, well integrated bass response).

Good luck

Start out with one of these pre owned and add another later
the units ship at 103 pounds weight ea and will out music anything listed above I promise.
The real advantage is a smoother in room response and blending your existing speakers by High passing your mains will dramatically clear up your whole system.
JohnnyR
Vandersteen dealer
http://vandersteen.com/products/model-2w-series-subwoofers

I replaced a REL Storm III with two 12" DIY Rythmik subs and cannot speak highly enough. For the price of the Rel I bought the two kits. And cannot speak highly enough about using two subs vs one.

I also use a Gallo sub but thought I'd get laughed off the site for suggesting it. It replaced a sub that was three times as expensive and within the first five minutes of use I thought it was a much better fit.
My other suggestion would be a James Loudspeaker sub. I owned an EMB-1000 a few years ago and it was fantastic. That sub always comes to mind when the "what piece do you regret selling" thread pops up.

Rhythmik is a line not talked about much that has some unique technology to recommend itself. I know at least one or two around these parts with good taste I'd sy that like them a lot.

Iv'e been reading a lot of reviews on psa subs made and assembled in Ohio, and Mj acoustics.From what I read mj acoustics is like what rel used to be.

Check out SVS.

I'm with Schubert on this. The Gallo subs are superior to any sub I've ever had including REL. They are also more compact than almost any other sub if that is important to you.

Those Gallo cylindrical subs are quite good.

You can get a new Rythmik F15 for under 1K, plus shipping. An F12 is even less.

I would find a used REL Britania series B2 or B3. Much better sub than RELs new series.