Thanks for the quick response.
I could go up to $250 for a pair of bookshelf speakers if someone told me something convincing about the low frequency response (bearing in mind that I probably will not get a subwoofer). I was, e.g., disappointed that the SM450s - that people say have nice bass - on sale at newegg for 250 are sold out.
So i'm looking at the SM350s.
I've also been considering a number of Polk bookshelf speakers: monitor 35b, 45b, and 40.
Also I very nearly pulled the trigger on the Polk floor standing 55Ts, because i read that the bass was good on them, but then i started having doubts that they would be significantly better that the bookshelf models in the bass department, and they're pretty huge.
I have an apartment in NYC, the room I'm talking about is small - about 15x20. My main purpose is playing music - mostly jazz. So I need some fairly strong and defined bass.