Alright, I got a JVC KD-AR480 headunit and it's pretty good. I'm new to the car stereo so I don't know much. Why do you need an amp? Now the question is.... is it worth getting an amp? I'm not rich so whatever I get got to be an average price. Would having a so so amp make any difference? Can someone explain this whole thing to me and give me an advice on what amp I should get (if I should get one) and what subs I should get.