does the stock xA stereo have pre outs for an amp and sub? i was planning on keeping the stock stereo for now and adding an alpine sub, just wanted to make sure i dont need to get an aftermarket deck... maybe its a stupid question but i dunno

 

get a high low converter and splice the speaker wires and you will be good to go

 

Correct, no direct plug in for a set of RCA's. You will need to buy a line level converter of some sort and splice into the rear speaker wires on the back of your stock head unit. They can range from relatively cheap to sky's the limit on price.

Look on ebay, there was a premade cable/wire harnesses that someone sells that will connect between your head unit and the wiring harness. It will provide you with preamp outputs.

 

http://www.edesignaudio.com/wire_pro...?productid=225

That + an RCA to reach from there to the amp is what you'd need.