Okay as you guys know.. Im installing an aftermarket sound system in my B6 A4. I have two problems that i need to know because im going to install it myself and id rather not deal with the pain of a dealer installing it.

1, What size and length wire do i need to run from my battery to the Amp? From the positive side of the battery or negative side?

2, Converting the stock head unit to RCA cables. I bought a little converter but i dont know which wires go where?

Thanks a lot guys!

 

Length, count on 20 feet... 16 to your amp, and another 4 for ground. As for size, that depends... 4 guage is a good bet for up to 1000 watts (if you get a high quality 4 guage) anything bigger, go 0/2 guage. If you're running a single small amp, like 300 watts or less, you can get away with 8 guage wire.

I have no idea about your RCA connector thing.

 

OKay because when i bought it out of my friends car which he had it professionally installed.. there was a 4 foot long 4 gauge wire and i thought if i run it 20 feet i might be in danger of burning it out. Thanks a lot though!!!!

 

Ok, as far the power wire situation goes, using 4awg wire, attach to the positive terminal at the battery and make sure you have an in-line fuse within 12 inches of the battery. You'll probably use at least 16 feet worth of power cable. DO NOT run it through your fender and through the doorjam; go through the firewall and then under the interior panels. Using a 4awg, you'll probably only need around 4 feet of it for your ground cable in the trunk. Don't forget you also need to run a remote turn on wire from the amplifier to an ignition wire so the amp will turn on and off with the rest of the car. As far as your line level converter, that needs to be tapped into 2 sets of speaker wires, generally the rear speaker wires...once you locate those, strip them back and attach the converter's wires into those, solder and tape them up.

EDIT: I'm adding a pic of how my amp wiring is hooked up at the battery so you can get a more visual idea.

 

A good way to run your power wire from the battery, is off towards the drivers side underneath that mesh plastic under the hood... it comes off very easily. Then, there is a grommet that is used for the hood release cable, push your power wire through that grommet, and your golden! It'll come out in a great place, down by where your hood release lever is... from there, run your power wire down the drivers side of your car... run RCA's and remote down the passenger side. And yes, you'll have plenty of room for the fuse under that black plastic mesh thing under your hood... and I used a 2nd fuse in the rear of the car.

Note the last pic, my power wire and fuse run behind that resevoir with the yellow cap, behind the coolant resevoir. The hood release cable grommet is at the far right of the engine bay, under that same long piece of plastic with the "mesh" in it.

 

Thanks a lot guys.

Do i have to tap into the rear speakers? Im pretty sure that i pull out the head unit and install a little box (converter) which converts outputs to RCA cables? Or am i wrong?


If im wong how do i connect the amp to the headunit?

 

I personally would say that it's better to add the line level converter behind the radio. You're more likely to pick up road noise from the speaker wires as they are not shielded or twisted. When you convert to a low-level signal and then carry the signal via RCA cables (especially twisted pair and/or shielded cables) you are going to cancel out road noise and/or block it from getting in the amplifier. On top of that, if you ever replace the factory stereo, any aftermarket stereo will have RCA pre-outs you can then plug the RCA cables directly into. Just make sure you DO NOT run any audio cables on the same side of the car as the power cables. I did power down the passenger side, audio down the driver's. You will run into many problems if you run the cables all together.

 

Yeah, but, if you run the power where I said to run it, run power down drivers side, and rca's down the passenger side. it is VERY easy to run wire in our cars... so it would be very stupid to run power and rca/remote together.

Also, spend $ on wires... honestly. Especially RCA's... I bought 3 pairs of street wires ZN6 or something like that (cant remember the name, but top of the line RCA from street wires) ... also used a high high quality 4 guage wire. I opted NOT buying an amp kit, because the fuses that are included are always tiny pieces of garbage... Anyhow, my point... good wires means the signal will get to your amp just like it left your HU... with no distortion.

 

I agree with that...I got the cable from work (thank god, 4awg can get expensive) and then ordered close to $400 in accessories from Tsunami; the 5 farad cap, distro blocks, battery terminals, etc. Quality cables are WELL worth buying. Now that I think about it, I spent more on my install accessories than I did on both my subs or my amp...

 

Fellas, wire is wire, There was a huge discussion on Carsound.com concerning this a while back with some serious car audio veterans.. Lots of items came out of that thread, some mostly dealing with misconceptions, marketing BS, and a few other items.. Most of the noise in car audio deals with faulty grounds or faulty solder joints..

But I will tell you to beware, with the price of copper these days, some wire is being sold slightly under that the gauge on the sleeve.. And if you are in a crunch for money, you can build your own RCAs using Canare Wire and RCAs from a good source (Parts Express usually carries a wide range) and you can use welding wire for power wire (it might not be the pretty blue, red, silver, brown wire, but it's very flexible, just cover with flexible braided sheathing and shrink wrap).