If you are adding an amp and sub to a factory premium sound system with its own stock subwoofer, you must get your signal for the line output converter from that subwoofer. Adding an amp and subwoofer to a stock radio can be the easiest way to improve your stereo system in your car, if you do it correctly.

Can I put a subwoofer in my car without an amp?

Subwoofers are designed to increase the bass frequencies, resulting in a deep, thumping sound. In most cases, they are paired with an amplifier to boost the sound. If you do not have the funds for both components, you can still hook up a subwoofer without an amplifier; it simply involves a little more know-how.