From MP3Car.com Wiki
[edit] How To: Wire Up A Car Audio Amplifier
For many people, installing a better audio system in the car, along with the CarPC, is part of the entire project.
Here are a few guidelines for installing a car audio amplifier in your car.
[edit] Basics
Your amplifier is a piece of electronic equipment. It needs to breathe, just like your pc. If you do not give it adequate room for this, it will over heat. While many high quality, modern amplifiers have built in protections for this sort of thing, it's still not a good idea to drive your amplifier to the point of shut down. Make sure that you place the amplifier in an area where it will be able to breathe.
You will need at least one set of RCA cables to connect to your amplifier. These cables allow for the transmission of the audio signal from the source unit (a head unit, or in most of our cases, a CarPC). The input on an amplifier is a low-level input. As such, you will be using the output on your after market head unit or processor to provide the low level signal. If running from a PC, there are a couple of options for the RCA wires. One is to just run a headphone jack to RCA conversion cable. Belkin is one manufacturer of these. Another is to use a higher end audio card which has the RCA outputs on it. A third is to use a headphone jack to rca converter and then standard RCA wires. In all cases the result is the same, an RCA input for the amp.
Some people want to retain their factory radio. If this is the case in your situation, you will more than likely not have a low-level output (RCA out) on the back of the head unit. This means that you will have to use an adapter on the high-level speaker outputs. This is the speaker wire coming from the back of the head unit. This is not a desired method as it tends to be very noisy.
Before you connect the RCA cables to the amplifier though, be sure to have your amplifier power wires connected to the amplifier. If you try and connect the RCA cables first, you risk a chance of the amplifier trying to ground through the RCA cables. This can potentially cause damage to other components in the car.
Another tip: Do not run your RCA cables next to your power cables. Doing so can cause noise form the power cables to picked up by the RCA (signal) cables. This can lead to noise in your music, which is no good.
[edit] Remote Turn On
Your amplifier is turned on via an ignition based source. For some cars, this could be the antenna, for others, there are built in ignition leads in the wiring in the car. You will want to tap into one of these wires and hook it up to the remote turn on lead for your amplifier. This will provide the amplifier with a switched 12 volt source. When the car is on, you should receive a 12 volt signal on this wire. If you have the power and ground on the amplifier wired up, this will allow the amplifier to turn on with the turn of the key.
[edit] Ground Wire
One of the first questions that people ask is what gauge wire should they use to wire up their amplifier? Check the owners manual for this. It should be clearly stated in there. Follow the manufacturers guidelines. If in doubt, go one size larger, as long as it will fit inside the terminals on the amplifier.
Now it's time to wire up the rest of the amplifier. For the ground wire, you will want to keep it as short as possible. The ground should also be the same gauge as the power wire, never any smaller. Make sure that your ground is solid. That means that it is contacting bare metal. Electricity doesn't travel very well through paint, grime, dirt, or any other such things. Scrape away a bit of paint for this. you won't hurt anything by doing so. Do not use seat bolts for grounding if at all possible. They are not good conductors for a few reasons. Many times, the threads of these bolts don't make great contact with their partner threads. This is thanks to paint, dirt, grease, and all kinds of grime in the threads. Also, may times, there will be carpet between your ground and the body of the car. Electricity doesn't travel very well through carpet (contrary to what you may think when you drag your feet over your carpet then grab the door knob).
[edit] Power Wire
For the power lead, you will want to add a fuse in line right by the battery. This is not considered optional. This is an industry standard, and as such, it should be followed every time an amplifier is connected. General accepted practice is to provide an inline fuse within 18 wire inches of the center of the positive battery terminal to the exit end of the fuse holder. To find out what size fuse to use on this power line, you should consult the owners manual again. If it tells you to use a 40 amp fuse, use a 40 amp fuse. Much larger and you are defeating the purpose of the fuse. Much smaller, and it will pop frequently, causing a big headache.
If you are installing multiple amplifiers, check the fuse ratings on all of the amplifiers and add them together to come to a total fuse rating.
[edit] Speaker Wire
Now comes the point where you will connect the speaker wire for your speakers to your amplifier. Many times 16 to 12 gauge is all that is necessary. If you are using a power hungry sub, you might even go with 10 or 8 gauge, sometimes bigger. I think that it goes without saying that positive goes to positive and negative goes to negative. A good practice is to twist the bare end of the wires. This prevents fraying ends from being exposed when you try and put the wire into the terminal on the amplifier.
For more information, see page: AMPLIFIER
[edit] Conclusion
Once everything is hooked up, you should be ready to turn the car on! Go find your favorite music and see our section on turning your amplifier for further instructions!
--Redgtivr6 15:51, 6 September 2006 (EDT)
