Is a Sub worth the bother?


I have a small, simple system that pretty much meets my listening needs. It's an NAD C715 (all-in-one deal) with a pair of Epos EL3 bookshelf speakers. I've been kicking around the idea of getting a cheap subwoofer with the idea that it would add a little oomph to things. This is strictly a music system, not home theater. I guess my questions are: 1) would a sub help that much or am I just limited because of the EL3s? 2) If a sub would help, would a cheap one be okay (I'm thinking along the lines of the Dayton sub 100, perhaps an Energy Take Classic 8--$100 at Costco these days). My room is roughly 12 x 20, but again, I'm not looking to bring down the house/neighborhood.

Thanks in advance for your thoughts.
comfortstarr
Try a Dayton Titanic from Parts Express. Not to pricy, sealed box, quick and articulate for the $$$.
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Agreed based on your system, a smaller sub will match with your monitors more easily than a large woofer. Where I don't agree is the 'cheap' part. A subwoofer is often overlooked as "they all do the same thing" which they don't. The subwoofer has one of the most difficult jobs in any system and 'cheap' subs simply can't do the job well.....well being the key here as a less expensive subwoofer or 'cheap' sub will just pretty much make noise and will overall detract from the great monitor sound. A good sub will add much to a system but a poorly designed sub most often the less expensive models will take away just as much. I would suggest waiting until you can justify the purchase a solid subwoofer and save time and hastle of a less expensive model. Just my humble opinion.
I'm enjoying my first sub which is cheap, and in my opinion, fairly good. It's a Polk which was barely over a hundred from bb on a half off sale. However, it seems to underpin my monitors nicely and add something i've definitely been missing. It's not the most articulate thing I've ever heard, but still adds considerably to listening experience.