Good budget sub for music?


Hello Audiogoners, looking for advice on a sub purchase

I want to spend no more than $500 new or used. Sub is just for two-channel music. I prefer musicality and accuracy to deep bass. I most likely want a front-firing sub. One question I have is about sealed vs ported--sealed seems better from what I've read so far.

I have an external crossover and will use the sub in a bi-amp arrangement with an NAD c320bee amp, where NAD gets nothing above 80Hz (I need line-level inputs). Speakers are the Ed Frias-designed AR.COM kit, with 6.5 inch Peerless woofers.

All suggestions appreciated!
abarnett
I'll second Johnnyb53's recommendation of the Mirage as a very good, inexpensive sub. I have the S-8 and it does a better job in a relatively small living room than the HSU VTF-2 it replaced. Very impressive performance for the money.
Abarnett,

Good question as I myself am looking for a subwoofer for my AR.com speakers. Anyway copied your post, and sent it to Ed Frias. Once I get a reply from him, I'll post it here on Audiogon.
Thanks for all the suggestions! I don't know anything about Mirage--will look into it. Cleaneduphippy, that's a great idea, I look forward to hearing what Ed Frias has to say.
Vandersteen - Used - Look up the specs on their website and buy the one that is designed for music and not home theater. Considered the most musical cheap sub.
Look at the Martin Logan Dynamo. Small footprint, sealed enclosure and it can be switched between front or downward firing. Very nice little sub.