I have 2 JL Audio 12" wo's and a JL Audio 250/1 Amp. i was thinking of going to subthump.com and buying the ttop box and putting these it, how would you wire these into the fatory headunit, would i have to buy one with pre outs?

 

Don't exactly remember what they are called, but you can get a "pre-amp line converter" or something. To put it simply, there is a little box that has speaker wires(about 4, R+, R-, L+, L-) coming out of one end and RCA's(female plugs) coming out of the other. You can wire the speaker wires from the little box to your rear speakers and then connect the RCA's(male plugs) from the Amp to the female plugs of the little box. It is a quick way to use your amp and speakers w/o having to get a new deck. Though, for optimal sound, etc. you will want to eventually get a new receiver. Hope this helps.

 

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