By extra power source do you need another amp or something to power the amp? If you need something to power the amp, first thing is to upgrade all your wiring, including doing a big three upgrade to your vehicle. Follow that with an aftermarket alternator and battery(s). If you need more amplification, the bb1400.1 is a strappable amp, so buy another one and strap them and call it a day. Otherwise get a good single amp like an American Bass VFL series or another SPL application type amplifier.