I have a 1994 Thunderbird LX with a V8. This is my first install for anything car audio related. I have an alpine 500w rms amp with a 12" 250w rms alpine sub, in a sealed box, installed in my trunk. I have my power running straight from the amp to the battery with a fuse near the end. I also have the RCA and remote wires running on the opposite side to my head unit. I also have my amp grounded to the frame. My problem is that my amp will not turn on when my head unit is on. Although, when my head unit is turned off, the amp will power on. It would also power on when I shut the car off, although this didn't happen every time. The amp would come on and the sub would start going. It sounds like a fast heartbeat. Some of my first thoughts where that the battery might not be powerful enough to handle the amp and the rest of the car at the same time, but I may be wrong. It will be fine if I have to get a new battery since I had planned on doing that sometime this summer. I just want to know if my problem is occurring because of me, or if it is because of the car. Any help would be appreciated with this. Thank you.