Car Audio wiring


Standard Member
Hi all,

I'm trying to wire in a second amp in my car. The first amp (JBL GTO 75.2 old version) is wired in by the car audio guys almost 10 years ago, using some Autoleads wiring kit from 14 years ago (recycled from my first install 14 years ago). I think it's 8 gauge wire, not sure about the fuse. Just bought a second amp (Mutant MT2404) recently. Not the best amp I know, but short on cash!

I was wondering whether I can wire the second amp from the first amp, and uprate the fuse, or whether I should run a second power cable from the battery with its own fuse. Also what fuse would I need if I go for plan A? I'm planning on bridging the Mutant for my front component set, and bridging the JBL for the bass box, so I guess I would be running max power.




Active Member
I am not a professional but have installed a good few cars but that was 7 years ago none the less will have a go!

Here's what I would do....
1.Run a 4 AWG cable from the battery to the rear using a cable splitter then run 2 separate 10AWG Cables to each amp.
2.Do the same for the Earth cable but from the back of the car is fine but must be bare metal ( might need sanding)
3. Run a good cable for the Remote and split it into 2 at the rear to each Amps.
4. RCA phono leads run it on the other side of the power cable. ( don't both together)
5. Fuse.. About 300mm from the Positive terminal of the battery the rating determines on the fuse on your amps Ie if one amp has 2 x 20 amp fuses and the other has 1x 40 amp = 80 Amps then you will need a 100Amp fuse ( always have 20 amp more than what your total amps fuse combined)

If you want photos I'll post here of a JBL install I did about 10 years ago to give you an idea.

Also check the battery to see if it can cope with the extra load if not then fit a power cap.

Other option would be run a another set of wire for the second amp.

Good Luck
Last edited:


Active Member
Best thing is to go to your local car audio shop (not halfords) and buy a distribution block. One input to many outputs.

They come in fused or unfused.

I have one of each for +ve and-ve inpupts but you can get away with one to the +ve and then just run your earth cable to another ground point on the vehicle.

In my old car I was running 2 amps from 1x 4AWG wire but people recommend running 2AWG or even 0AWG to the block then 4AWG to your amps

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