The easiest way is a Line Out Converter. you either splice off the rear speakers or if it was equipped with subwoofer then you can splice into that line. The Line Out Converter just gives you a set of RCAs and then you just hook it all up like normal.
Where is factory stereo amp located on a 2007 Cadillac cts
No, you can't. It does not have such cable at all.
A 2007 Chevy Avalanche will only have an external factory amplifier if it is equipped with a Bose stereo system. If there is a factory amp included, it will be underneath the center console.
I have no answer for you but mine does the same thing.
Use a line out converter spliced into the rear speaker wires to connect RCAs to a sub amp.
Hook your speakers up to the amp.
Put the E.Q. between the pre amp and the main amp.
What part is required to connect a mono amp to a factory stereo
There is an amp only if equiped with factory infinity stereo with 7 speakers. If so, the amp is behind the glovebox.
it built into stereo
well you hook it up
No.