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
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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.