A battle between JL's
 

My friend; 12W7, ported box, JL Slash 1000/1v1, 0 gauge wire, Optima trunk battery.

Me: Two 12W6, dual ported box, JL Slash 500/1v1 to EACH sub. 0 gauge to 4 gauge wire. Two Kenetik 600 watt batteries. One to each amp.

He thinks he can blow me away. That I'm no competition. Now, I might not get as low as the W7. But I'm pretty sure I'm going to be overhitting him on some many levels. Opinions?

well both are great subs, but all else being equal or close to it...the boxes are both designed properly, the cars are similar enough, and everything is working right. You should win. You essentially are giving the same power to twice the surface area, and even though the w7 has more excursion, it would have to work a lot harder to move the same amount of air, which it won't even at max excursion (29mm vs 19mm for the w6). Strictly from a piston moving air point of view, it won't move as much air as the 2 w6's. Of course, most things in real life aren't equal, so I guess you'll find out soon enough. Good luck!

Virtually the same equipment (1k / 1k), you win with 2 12's.

Box's have a lot to do with it in this comparison as well.