Yea, youre not going to need a 2 gauge wire for that. 4 gauge will be more than enough + some overhead. And if your electrical system is in good condition, you shouldnt even need a cap.

With that said, I think you should pick a different subwoofer or get a bigger amp. The W7 is a huge beast. It likes a lot of power, and I think for the price you pay for it, you would want to take advantage of that. 500 watts isnt going to cut it. I think if you were to keep that amp, getting a smaller, less power hungry sub would be a wiser choice.

 

sorry, it was a 10" JL audio W7 not a 12". and what would you suggest to power that sub if it has to be kenwood excelon series of amp?

 

Kenwood makes a hell of a HU but there amps are so so. If I were you I would go with a bigger name in amplifiers than Kenwood like Rockford, JL audio, Precision Power, Audiobahn, MTX etc.