Best musical sub around $1k


Looking for some advices on sub.

I am deciding between Sonus Faber Cremona Auditor + sub or go full range and get Cremona. If I were to go with Auditor + sub, I will need to keep the cost down for my decision to make sense, hence the $1k budget. I like the stregth of mini-monitor - imaging, better coherence (2-way vs. 3-way), and easier placement. But Auditor needs to play loud to sound full range and I don't have that option most of the time due to my power amp (BAT VK-75SE) and small kids. So getting the Auditor will require a sub for my need.

So what sub will you recommend? I had a REL Stadium III before, but price is out of my range right now. Cremona sub is also too expensive. Are the smaller REL as good as Stadium III or I am better off getting an older Stadium (II ?)

Or to complicate the issue further, get a floor standing Cremona instead?
semi
i would have to say the best sub in this price range would have to be def tech's super cube 2.. if you could afford the super cube 1 that would be awesome but the super cube will knock your socks off..
Just picked up a REL Strata under $1k to match with my Sonus Faber Grand Piano's and it made a SIGNIFICANT difference. The result was much more than what I've expected, with increased dynamics, more holographic imagery/airy, and the ability to produce tight/punchy/fast bass with great definition and clarity. I would say it's a seamless integration to my GP's. Probably one of my best upgrades in addition to the Cary cdp. I totally recommend it.