Originally Posted by SumAccordGuy94

You may want to start with a 4 channel amp for your main speakers, and see what they sound like then. It wont be amazing bass, but you'll have good mid-bass and you'll be able to play them louder without distortion.

Originally Posted by rcurley55

Personally, if you want to go loud, you will need a few things. First, I'd recommend more power to your speakers. Also, you will need a crossover to take the bass out of your small speakers and redirect them to the sub.

If it was me, I'd get a 50x4 amp. Run the front 6.5"s from it, and then use the other two channels to run a single sub or a pair of them. Then run the rear speakers off of the headunit.