Im sure there is a simple answer to this and im pretty sure i know how to do this but i just want to make sure of it.

How would i go about running my amp off of a seperate battery from the one used for the car?

If there is already a thread on this could someone please direct me to it. I added more audio stuff to my car and i need to run my amp from a different source.

Also is there any way to run my headunit off the other battery to or would that cause it to never turn off even when the car is off?

thanks for any help.