i understand that an extra battery is used basically for "park and Pound" correct? however why then do high end car audio guys use 10+ batteries in their system. I have a rockford fosgate t1500-1bd running at two ohms at 1300 watts for my sub, and two rockford fosgate punch 200.2 amps to power my speakers. i only have the t1500 and one 200.2 hooked up at the moment, but when i put in the third amp will 1700 watts require a second battery? right now my lights dont dim at all.