Car Audio Amplifier Wiring Kit Guide
This article is about car audio amplifier wiring kits and what they contain and how to set one up in your car. The reason for wanting a car audio amplifier in your car is to drive a subwoofer or to provide added power and control to your speakers. Maybe you want to have a subwoofer and power your speakers from amplifiers. Regardless of which combination you want, the basics of what you need remain the same.
The first thing to check is if your head unit (CD player) in your car has a pre-out which (low voltage standard audio output) can be used to connect it to a car audio amplifier using a wiring kit. This connection will be on the back of the head unit and they will be phono connections which are usually red and white, although they are sometimes red and black. These are like the connections you might find on your home stereo or TV. If you really don’t know what I mean, just google phono socket and look at the pictures. If there are multiple phono connections on the back of the head unit, they are most likely labeled. You will probably find front, rear and maybe AUX subwoofer. The AUX connection will be an input, the others are all outputs to the relevant areas of your car. For the purposes of this article, we’ll assume you’re using a head unit with a single output, as this is what most will have.
When using a head unit with a single phono output, chances are the signal can be switched between full range and low frequency. The full range would output all of the sound, while the low frequency setting would be the setting to connect to a subwoofer.
There will also be a remote cable on the back of the head unit, usually blue in color, but I’d recommend checking. This information is located on the top of the main unit on a sticker or in the book that comes with it. This remote wire tells the amp to turn on when the head unit is on.
The first thing you should do is disconnect the battery to eliminate the risk of causing any damage to the car’s electrical systems. It is very important that you do this as some damage can be expensive to repair and it is always best to minimize the risks. The last thing you want to do is blow up some components on your new amp or set off some air bags.
The ground wire should be connected from the amp to the chassis at a point that is not painted, for example where something is bolted to the chassis. The ground wire is the large black or brown wire that should be the same gauge as the red wire.
The power wire, which is the big red wire, should be fed from near the battery to where the amp is, don’t actually connect it to the battery yet. It is important to have an in-line fuse installed somewhere along this power cable. Make sure it’s in an accessible place, usually near the battery, but that’s not always possible. The important thing is that it is relatively easy to change if necessary.
The phono output of the main unit must be connected to the phono input of the amplifier using a phono cable. Phono cable is a double length of coaxial cable with phono plugs at each end. When you run the cables, make sure that the phono cable is at a reasonable distance from the power cable, as this will prevent any interference.
The remote cable must also be connected from the main unit to the amplifier. This will be clearly labeled on the amp.
Next, the speaker cable must be installed. This is a double length of unshielded cable, which is probably quite thick. The power that will be used to drive the speakers will determine the gauge of wire required. When you connect the speakers, make sure they are connected in the correct direction; otherwise, it will reverse phase, causing cancellation and a reduction in sound at certain frequencies. By this I mean making sure positive goes to positive and negative to negative for all speakers. If you’re only connecting a subwoofer, this isn’t as critical, as you can usually reverse the phase using the amplifier, which will solve the problem.
Once you’ve configured all the cables as described above, it’s a good idea to check them to make sure everything is okay. If everything looks good, it’s time to reconnect the battery and also connect the red power cable to the battery. Once this is done, your new amp should be up and running. All that remains is to configure it correctly, but that’s for another article.