I hooked up a Sony xplod 600w using speaker level inputs to an OEM head unit, Boston Acoustic speakers all around. I had to adjust the gain to make it sound half way decent. Output of the head unit is just too weak and the amp didn't have enough adjustment to make it sound decent for my taste. Mine was the 2000 model single disc with controller unit. I suggest you save up for a nice 4v head unit with 4 rca outputs and 2 preouts, mate that to a high quality amp and speaker setup. Why throw good money after a inferior setup? There are some nice double din systems out there that do all kinds of stuff...just be careful if you shop on ebay. Good luck!