subwoofer question

need help in choosing a sub for small room which would connect to a rega brio amp and dali ikon 2 speakers- thanks.
I have a question. I have a pair of Dynaudio 1.4`s and a contour center and am in the market for a sub that is musical. I`m looking for clean tight deep bass. Any suggestions. ? My room is 12x18.
I recommend the SVS Sub Ultra 13. It is a powerful sub, well built, great performance and on the money!
Google it and get all the info. I have two of them and I regulate them with a DS Peaker 8033. Everything in my room shakes, great for movies.
In a small room , I would be cautious about introducing any subwoofer into the equation.

First and foremost, first try out any quality sub on a dealer or buddy loaner ... You may be surprised that it is a step back overall with a boominess or a wooley overemphasis simply because of room acoustics in a smaller room and restricted speaker placement alternatives.

Subs for HT are one thing, but adding a sub for quality 2 channel is a difficult alchemy. The good ones are all well north of $1500 w/o prejudice to the acoustic issue above.
It's going to have to be a sealed enclosure rather than a ported one.

Google the reviews,
Vandersteen 2Wq and ATC are two that I would audition ... In that order.
Google the forums for their testimonials.
E.g. The Vandy has three 8" drivers instead of one big one and its external crossover accessory is easier to tailor to the gear and room parameters.
The PSB's are great. Very musical and inexpensive for a smaller one. $300 to $400 depending where you get it. IMO, can't be beat for the money. I've sold a bunch to friends and family.

I agree with Morganmadden. SVS has incredible products for the money and will take anything back within 30 days no questions asked; and even pay for the shipping going back. I did a 7.2 application with two of their sealed subs and the capability of these units are remarkable (to say the least).
Small sealed REL. I have a Q108 in a small room. You don't even know its there....until you turn it off. Fast, tight and unobtrusive. I use it for music only.
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I second the REL suggestion and found that setting up my Q150e (10" 150
watt bought used for 200 bucks) in a medium sized room was easy. Move the
REL around until it sounds good, don't turn it up too much, and adjust the
crossover level to blend with the lower range of your mains. I'm not a fan of
"Room Mode" correction gizmos as they add extra wiring detours on
the music signal, impose some geek designer's opinion of what's
"correct" and can be a waste of money if you own furniture. A REL's
"high level" input utilizes the sound of your amp without bothering
the mains speakers (or the amp). Most REL users find that the ambient presence
of these (or any good sub) somehow "pressurizes" the room making
even bass shy recordings feel better. If setting up a REL provides "difficult
alchemy" you need to get out more.