SIVADSELIM: (Kind of Blue was one of the CDs I tested last night; I figured that if the low-end sounded weak on that, then something is going on.) Yes, fronts are set to Large, with No Sub selected.
The center definitely seemed to help with dialogue in TV/movies, but I can't say whether I had the receiver set as having no center before I added it. So, if it was set as having a center while I actually didn't have one, would dialogue have been really difficult to pick out, and should dialogue be better now without a center (and set at no center) than with this RCA? If so, is the RCA really that bad? I just figured that for something like dialogue, what's the harm in having a cheap center?
AFROGT: I would really rather not spend anything on a sub right now; missed a golden opportunity at Christmas! When I do, I'd be interested in something pretty affordable. I've never owned a sub, so I don't know what to look for, what price-point would be sufficient, or what to pair with these speakers. Completely in the dark, here.
Anyway, thanks for the input!