As a long time condo dweller, I've not been able to use any of the great large subs, so I have tried well over a dozen well reviewed compact subs from Carver, Sunfire, Velodyne, ACI, M&K, Legacy, PSB, etc.
By far the very best sounding of those I've tried is the James EMB-1000, with a 10" active woofer and passive radiator, a 600 watt amp, and a totally unique loading scheme that produces strong, palpable bass to near 20 hz. without boominess or obfuscation in a 12.5"x12.75"x16" package. List is $1595 in black; my price for a 3 month old sub is less than 1/3 of that, inc. shipping to cont. US!




Stereophile and others have reviewed the EMB-1200 and others have too.
http://www.stereophile.com/subwoofers/904james#lkEzfdT2xkTifzhy.97This is fast enough to blend with the best low coloration speakers out there. I used them most recently with my Deadalus DA-RMas. This sub is 3 months old, and was a flat black sub that has had the sides covered in 1/4" solid walnut staves. Looks OK, but not great.
I've recently simplified my setup, sold my Daedalus speakers that I had used with these and have gone to full range speakers.
If you've been looking for a small, very high quality sub, this is the model to try.
Free shipping at my price to cont. US only.
Thanks for having a look.