Right now i have a 1500 Watt amp and 2 12" Sub woofers (And new door speakers(don't know if that matters)) And when I have the music all the way up, each bass hit dims all the lights on my car. Now I want to add a 15" and another amp, but I'm not sure if it will be able to power it fully. What can I do to ensure everything receives maximum power? I heard something about needing a better alternator and a better battery, but I don't know. Thanks for any answers!