I've been wondering about this as well. I just didn't bring it up because it's a long ways down my toy priority list. Besides, the JL 12w3's (sealed box) are the one subwoofer I own that's actually working fine. Mostly, I've been thinking I'd like to replace that box, along with the subs, with a nicer single sub in a smaller box so as to reclaim some trunk - and more importantly the back seat pass through. I've never measured the output in my car, but it's "enough." I don't go to competitions, I just like clean, strong, musical bass in the car that will give me a kick in the chest when I want it to. I don't suppose anybody thinks a 12" servo sub in a 1.2 cu. sealed box would keep up with a pair of 12w3's powered by an old school MTX 500d? As asked above, is there a 12v solution for the amp?