Tight bass sub recommendations

Another vote, Vandersteen.

With my Maggies I found if you keep the crossover point low and volume low you can get a half decent sound and rid of a lot of hangover even with a lower end sub.

I have been trying dozens of different high quality subs in my small room to try to find the best match with speakers like the smaller Maggies and Reference 3A monitors I have been using. My favorite by far for QUALITY bass has been the little Totem Kin subwoofer. It is -3db at 29 hz, and has the smallest footprint by far of all the subs I have tried (the enclosure is only 1/2 a cubic foot!) It uses a very rigid 8" carbon fiber driver in a sealed enclosure. For pure definition and completely uncolored bass that is fast and tight, this is the one. It bettered my previous favorite REL T-7i, in the way it actually improves the lower midrange of the music, as well as the detail in the bass. The other subs I tried got quite muddy in that area when I set the crossover much above 50 or 60 hz. If I set any of the other subs crossovers at 90hz or higher, they all did very negative things to the music. I can set the crossover on the Totem Kin sub anywhere between 120 and 200hz, and it does nothing but compliment the lower midrange and bass, making grand piano recordings and powerful brass horns sound more full bodied with no mud whatsoever, even in my small, often bass problematic room. I like the fact that turning the sub "on" does not make me first realize that the  bass is 10hz deeper or more powerful than without it, but that my midrange actually sounds better!  

People get too caught up on brands in these kind of threads. 

I mentioned Rythmik, but I also have Power Sound Audio and SVS and have owned HSU and others.  There are a number of other brands I'd be happy to own.

What's more important is getting the right sub for your space and intended use.  Nobody has asked what your room volume is, what your placement options are, whether you also would like to use it for home theater, etc.  Those things should drive your purchase decisions more than what brand you buy.

All of the brands I've mentioned have people that are easy to get a hold of and are very knowledgeable.  Of course they will recommend their products, but once you get an idea of what size/type/output you need, then you can comparison shop.  These are all internet direct, but you can do the same with your local dealer. 

Get advice about what you need, not what brand someone thinks is "best".  It's almost always the one they bought, which may not be the "best" for your situation.

@big greg, 
It isn;t the brand, but how the sub works with the speaker. Vandy's use an external crossover to cut off the speaker at low frequencies and letting the sub do its' job, so there is little overlap which would degrade sound quality.
It also relieves the amp from having to reproduce the lower frequencies, which are the most demanding.
B