What kinda JL is it? You should either get another one, or get a really good 12". I recommend a W3 or if you have lots of cash to spend get a 10" W7. JL makes fucking amazing sub woofers. The ampage sounds find though. I mean it definitely wouldn't hurt to get one good amp rather than two "less good" ones.
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I stay high all the time, i'm on some hood shit
Give me some dro, purple haze, and some chocolate
Give me a dutch and a lighter i'll spark shit
And stay high all the time, I smoke that good shit.