I'm a noob when it comes to this stuff I am totally new an I'm curious on building my own portable Bluetooth speaker? I was thinking of building a box with a 12V battery 7ah? With 6x9s an then 5 1/4 speakers with a stereo unit that has Bluetooth my question is how do I add on an off switch an on? An 2nd I'm gonna add in a amplifier which is a board amplifier would I need a two channel amplifier to power the speakers an stereo or a four channel?