I have a 2004 chevy tahoe with stock battey and stock alternator. My tahoe has a in dash DVD player and I have 3 12 inch kicker L5's I was wanting to upgrade my amp and get a couple kicker amps so that my subs will actually get pushed because the amp I have now is just not doing it. When I do add the 2 amps I am afraid it's going to suck all the juice out of my battery when I play it. So I don't know if I should just add another battery or if I have to upgrade the alternator first so it can charge 2 batteries without a problem. Just let me know what you think, any input will help, Thanks.