View Full Version : Dual battery setup, power amps and...?

04-14-2011, 02:04 PM
Doing a dual batter setup to power the stereo, im going to run the amps off of the 2nd battery. My question is should I also run the head unit off of the second battery or allow it to run off of the main?

Double D
04-14-2011, 02:40 PM
I would say second battery. That way nothing is really draining down your battery that starts the boat. Thats the way I have mine hooked up. Even the memory line is to the second battery.

04-14-2011, 03:38 PM
If you have a dual battery switch then everything (except possibly memory, a bilge pump and float switch when applicable) should run to the switch common post including ALL stereo electronics, helm buss and the alternator/starter feed. No exceptions.
If you are running an ACR/VSR then you may run ALL the stereo electronics off a dedicated stereo bank or the house bank/battery.
You never want the source electronics and amplification running off two separate batteries. Any difference in voltage potential will attempt to level via any path that circumvents the dual battery isolation. In this case it would be the ground shield on the connecting RCA cable even though it may terminate into 10Kohms above ground (its still the lowest path of resistance). This can result in noise and passing DC current on the RCA shield can also be harmful to the source unit preout stage.

Earmark Marine

04-14-2011, 04:29 PM
I agree. All of second battery. And just from my current situation I would suggest a good starting battery on your 1 and a deep on your 2nd. Your #1 battery imho should be for running the boat not running the toys that you don't need to get back to the launch

04-14-2011, 04:32 PM
On my boat I went the route that EarmarkMarine is suggesting. Put in two batteries and run them to a Perko 2 battery switcher. This will allow you to run on battery run(cranking battery), battery 2 deep cycle while hanging in the water drinking beer, or both if desired. NOt expensive to do and allows you to completely control what battery you are pulling juice from or pumping juice to when running.