Adamou, thanks for the reply. I have an Alpine cassette head unit with a trunk mounted Alpine 6 disk changer.

I've seen some pretty big capacitors in the Crutchfield catalog. If I understand their application correctly, caps are useful mostly if dashboard lights dim on heavy, loud bass notes. Capacitors *do* store energy. I was thinking that the cap might not be the best idea to have on the constantly "on" line to the head unit because, the cap will store a large amount of energy and this might be problematic when trying to start the car. I could foresee the radio fuse blowing if the cap tried to help "start" the car. So, I think the cap wouldn't help run the CD or head unit while cranking, and I don't want to have to remember to turn off the head unit each time.