To the OP - For $200 it's going to be somewhat challenging to get you what you're looking for. I had the JBL sub you are asking about for a while - ask Mazer - and I ended up returning it. I was trying to spend as little as possible and still get a great sound.
The JBL Sub 12 looks nice, but its performance leaves a lot to be desired IMO. It has no detail, and below 60-70 Hz, notes become indistinguishable. I don't think it was able to even reach it's rated spec of 25 Hz with any significant output, let alone down to the low 20's where you're aiming for. Very sloppy and boomy, despite its impressive wattage, and LOTS of port noise.
I don't know if I can suggest an alternative for you in the $200 range, as I ended up having to spend the extra bucks on a good SVS sub which has done me VERY well so far. But I had the cash to spend at the time, it may not be as easy in your case.
I hope this post helps - not trying to slam JBL for the sake of slamming them, just trying to help you avoid the exact same scenario I found myself in several weeks ago.
Those Dayton subs get really good reviews and might be in the price range you're comfortable with. Just make sure anything you buy direct from the internet has a return policy.
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