dalton54

do i have to upgrade the head unit to install subs, i have looked all over and can not find any info. thanks four your time

Chromeshadow

There is a lot of info in the Electronics section : https://mustangforums.com/forum/audi...lectronics-28/

The short answer is no, but the factory head only has speaker level and very low level outputs. Most people who add amps use one that takes speaker level inputs or use an adaptor that converts speaker level to line level.