i don't know much about car audio installation but i will share what system i have.
* 2 rockford 700S powering both solo baric 12 L7's
* 1 RF 500X for the front and rear speakers.
my lights used to dim even with low volume. i have then a yellow top battery and two 1 farad capacotors. my friend then installed a second yellow top battery at the trunk which i think powers up the system because he installed two circuit breakers (one in front after the 1st battery and one at the trunk before the second battery). when i turn of the circuit breaker the system totally shuts down but the receiver still works. i don/t understant the whole set up but i hope you'll get an idea with my system set up.