Heck with the 3 12's. I'd say if it is a small car, get a single 12 or a single 15, but make sure it s a good sub like Digital Designs, Blueprint, Shocker, Treo, or some brand of sub they use in db drags and such, a real high quality one. Get a lot of power for it also, I mean lots. 1000 wattts just don't cut t these days. In the right ported enclosure, a single sub would kill any of the options she was thinking about. Spend the money on a good sub and amp, build the box right, and you will have a nice, hard pounding system.
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