stereo and speakers

What model, what year?

If you are installing aftermarket head unit and want direct speaker lines, then unplug that fader and splice all the wires to that fader harness wires... remember,

4 wires will come from the head unit... two channels...and the remainder 8 wires are the 4 speakers.

Interesting, so it is actually not using all four channels from my aftermarket system to fade the speakers from front to back? I think I may have to do a little re-wiring to see if I get better performance from my head unit. Additionally, do you find that the fader tends to add a lot of loss to the system?

On a related note. What path are most of you using to run the power, preamp signal lines, etc. to the back for adding amps, speakers, and subs to your Mercedes? Is it best to go along the driver side or the passenger side? And where the heck can you get through that firewall with a 12V line directly from the battery for the amp? I am seriously considering adding the sub and some additional speakers now, and I can already run into these problems in the planning phase.

If you are running an external amps on all speakers, then forget about the fader switch. Run all new wires from the amp to each speaker location. I find it is easier on the passenger side for Mercedes to fish new power wire and preamp cables... Speaker wires can also be run on the same side to ease the installation.

Exactly, if you just plug in the factory harness, it is only two channels... unless you got a later 86 or newer that has external amps for front speaker.

You will know if you got two or 4 channels head unit by counting how many speaker wires... if it is 4 then it is two channels... if it is 8, then it is four channels.

Fader will lose power and clarity, but sometime that is necessary to balance out the system.... that is without external amps. With external amps, you can balance it out by the amp adjustments.

I have an 1989 560SEL

Then you would have 4 channels at the head unit... front two speakers are on MB external amp...