I have a Sundown saz1200D for my subs and a JL XD 400/4 for my components in my 2004 f150. I have a big 3 wire kit and still getting voltage drops. I'm trying to decide If I should run a second battery of a HO alternator.

 

Your voltage drop is caused by the demand on your electrical system being too high for the alternator's output. Adding another battery will just increase that demand. You need a higher output alternator.

- Jack

 

^^^^ x 2 ^^^^^^

 

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