All I can think of off the top of my head is a dedicated ground channel to reduce crosstalk, but it's just an amp so that shouldn't matter...?

 

It's a common way to reduce electrical interference in low power signal circuits.

It's basically a 'wire cage' around a group of conductors - this 'cage' is held at ground potential, and 'shields' the internal wires from outside signals. In a sense, a 'tin foil hat'

The shield is connected to ground potential at one end of the cable only.

See this for more information about the whole idea.

 

I believe it's for the AUX cable, since it passes other power wires on it's way to the location above the glovebox or into the center console it helps to reduce stray signal noise or crosstalk like Twilight said

 

What are the 7 components?

Front left and right
Rear left and right
Sub
=
6
?

(oh you must be putting in component speakers with separate tweets.)

 

7. all 4 door speakers... the 2 tweets in the pillars, and the sub. 7. you have a 2007 too, you should have 7 speakers too.

im going to drop the aux input.. i have a ipod cable for my dnx5120.. so the mini jack is going out the window.

so since im not using the factory amp, or the factory AUX port, i could prolly leave the shielding off? there's not a wire on the back of my HU that says "shielding".