Rockford Fosgate Punch 400 Watt Full-Range 4-Channel Amplifier - PBR400X4D

In this buying guide we go over the basics of finding the right amplifier for your car stereo system. When you're putting an aftermarket stereo system in your car, it's important to have the right components. An amplifier supplies your system with the power it needs to run your speakers, making it one of the most important components. Choosing the wrong one can hinder what your speakers are capable of.