I just got a new 12" alpine subwoofer and two amps and my headlights and dash lights are dimming with my music. I know i need a new alternator(was tested with no music) but i dont know whats any good or whats not worth purchasing. I might get a capacitor but im not sure how well it would help vs getting a new bigger battery. Plus i wouldnt know what the best option might be. Help me out if you can guys im new to all this and dont know much about all this.