Do I need a subwoofer? Which brand and model?


I mainly listen to classical and jazz - mostly trumpets and violins, with the occasional piano, viola or bass guitar. A couple of my friends have been suggesting to me that my ensemble lacks bass and having a subwoofer will address it. My setup includes a 2 ch. NAD C365BEE integrated amp, Wharfdale EVO 50 loudspeakers (pair), and an Oppo BDP 105 Bluray player as a CD player. The setup is in the living room, with three walls, and the fourth side open to the dining room. The living room itself would have been 18' L X 12' W X 18' H = 3888 cu. ft, but the fact that it opens up to the dining room makes the entire space more like 40' L X 18' W X 12' = 8540 cu. ft. Would I benefit from a subwoofer and which one should I get? Budget $1000 or close to that.
shugho
I apologize for not mentioning in the last comment that Bob Reynolds is already recommending the SVS SB2000 over the Hsus for my system. Any other comments specifically towards these three models are welcome.
Lloyd, you mentioned about having setup options. The Hsu VTF 15H offers more options with regard to fine-tuning, according to what I understood from the web site. I am somehow leaning towards this model from a power and flexibility standpoint but also feel that I will be taking a risk with this model. The reason it is a risk is that this model is beind sold at a discount and there is no return policy on it. I feel that the SVS SB 2000 is the safest bet because of their return policies. However, I am leaning towards taking a risk with the Hsu VTF 15H. Not sure if this is the right thing to do. Any help is welcome.
"However, I am leaning towards taking a risk with the Hsu VTF 15H. Not sure if this is the right thing to do. Any help is welcome."

Don't get them both at the same time. Do the amp first, as it may have an effect on what sub you choose. Also, you may find that you don't need a sub with the added power.
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"11-30-14: Bob_reynolds
Since music is the priority, a sealed cabinet would more likely be a better choice. And there is no reason to get a power amp. You do not want to drive your main speakers more -- this only creates more distortion."

No offence, but that's silly. There's more to audio than reading a spec sheet. And in this case, you're guessing in order to fill in the blanks. In the real world, you're far more likely to get a speaker to distort by under powering it. The OP has a big room and his current amp, while of good quality, is not all that powerful. If a speaker has to be driven harder than normal because the room is big, its far safer to do it with a more powerful amp. You'll get less distortion, not more. (Unless, of course, you're foolish enough to push the system so hard, it starts to break up. After reading the OP's comments, I really don't think that will be a factor here.)

Take into consideration also, that driving the OP's current speakers to their potential, will make it much easier to integrate a sub. The integration works both ways. Just as you can push an amp and speakers into distortion, the same can happen with a subwoofer and the amp that powers it. In fact, you're much more likely to have a distortion problem with the sub, as opposed to the main speakers.