For this 2020 Honda Civic Si we upgraded the door speakers with JL Audio 2 way components. Added a 12 inch subwoofer in the truck housed in a ported enclosure to create more pressure. The sub is powered by a 250 watt JL Audio mono JX series amplifier. These subwoofers are super efficient so they don’t need a lot of power. In fact they outperform many power-hungry subs in their class. This car sounds awesome!