Im getting ready to install my new system soon but I ran into a couple problems/questions. I am going to be running a Fi Q 12d2 parallel to a Sundown SAX-1200D. Im going to be adding this to my stock setup in my car. I have a 2010 Audi A4 without the B&O system (it has the basic system). Im going to have a ported box in the trunk. My main question is... What is the optimal way for routing the Sundown's RCA's back to the head unit without problems? I've seen people in previous installs on the Audi forums that simply disconnect the stock sub, then splice the wires, and add a converter to female RCA. They plug the new(sub) amp's RCA's to that which routes it back to the stock amplifier and back to the head unit. This is probably the easiest(laziest) way to do the install but I was wondering if this will give me my full output. I wasn't to sure on wiring a powerfull amp to a less powerfull stock amp for the head unit to read proper signals. Ive seen people use this line output converter to route those RCA's. http://pac-audio.com/productDetails.aspx?ProductId=175&CategoryID=28 Second question is do you recommend I do the Big 3 for this set up? I already have 10 ft of Stinger Hyperflex 1/0gauge wire. Thanks for the help If you have any questions don't hesitate to ask