Ok, so im not new to the car audio world I have always had some kind of a system in my car, however, I am new to having a serious audio system. I just recently traded in my trailblazer ss, (gas prices were killing me, lol), and bought a new 2012 malibu lt. In my truck I had a double din pioneer touch screen head unit, which I sold as I decided to keep my stock head unit in my malibu. Im moving the remaining parts of my system into my new car. Getting a new box built for my 4 memphis pr 12" subs, moving over my 2 memphis 16-pr1.1000 1000watt mono amps, and my 2 1far. power caps, (and will also soon be replacing my 2 6.5" door speakers, and the 2 6x9s in the rear deck and adding a highs amp, eventually. Still working on the lows right now.) Now, this is where my dilema comes in. I was thinking of adding a line driver,.im assuming I will need one as im running all this off of a stock head unit. Right? Or should I go with an epicenter? Or both? And.also, once I upgrade my highs, and add the highs amp, should.i add in an eq? Im thinking I should, cause again im working with a factory stereo. What about a crossover? Im completely lost when it comes to all that extra stuff. I usually just have a head unit, an amp, and a set of subs. Lol. Someone help me out here, what should I get? Or what do I need for maximum sound and best quality? And for the record I go to audio unlimited in my home town and get everything hooked.up and tuned professionally. Just need to know what all I should buy and.take up there to get installed. Trying to compete.in some audio competitions next summer. Thanks guys.