help with car audio installs

[Gizmo]

12vDC has a much worse line loss coefficient than 120vAC. 12vDC can lose up to 1.5v in as little as 4' dependent on the current draw. Just an off the scale example. This is why they run 500,000VAC from the power plant to a city substation, the higher the voltage, less current required, and thus less line loss. If you had a car amp pulling 40+ amps u would end up with a higher voltage drop than a trunk light running at a quarter of an amp.