When installing an amplifier, every car will present its own challenges that you will need to overcome. This guide will help you to do it correctly, and safely. When dealing with a car's electrical system you need to always have fail-safes. Those being the fuse located within 18" of the battery of the car, as well as the fuses that are built in to many amplifiers.
NOTE: Just because the amplifier has fuses on it does not mean you do not need one near the battery!
Getting Started
The first thing you always want to do when preparing to install an amplifier in your car or truck is find the location that it will fit, conveniently, with enough air-flow around it to keep it cool which is especially important on Class A/B amplifiers which tend to be less efficient and in turn produce more heat.
Pre-flight check
Once you have determined where you think the amplifier will be accessible, yet out of the way, it is time to do our pre-flight checks. Just as a pilot needs to check things on his airplane before takeoff, you need to check to make sure you have the proper tools and equipment for the install.
Do you have the right size wiring kit for your amplifier?
Not all wiring kits are equal! With wire you truly do get what you pay for. Just because that kit you saw at the local shopping center in the stereo aisle right next to the tire center, yeah, you know the place, was $15 and says it can handle 1500 watts doesn't mean it can. You want to make sure that the wire in that kit is high-strand count, and hopefully, but not always, OFC (Oxygen Free Copper), and lastly, make sure it is measured in AWG (American Wire Gauge). If the packaging does not say "AWG" on it and just says "10 Gauge" the wire does not have to live up to AWG standards. I have seen this personally when comparing our Stinger HPM wire to lesser quality wiring. Our Stinger 8-AWG was larger, and had more stands, than this other companies "4 Gauge".Do you have the right fusing, battery terminals, and wire terminals?
In order to effectively and correctly install an amplifier on a GM vehicle, special side-post terminal adapters are needed to allow the addition of the power wire's terminal to be bolted to the end.
Also needed, are the ring terminals for the power cable/fuse and depending on the amplifier, possibly forks for the speaker connections.
Got all that? Cool, lets move on to the actual installation.
Step 1 - Power Wire
Now we need to run the power wire from the battery to the amplifier. To do this, first Disconnect the Negative Terminal of the Car's Battery! After making sure power to the vehicle has been disconnected, cut a short piece of the power cable that is long enough to reach the fuse block where it is secured and out of the way of moving parts. Crimp one end of the power cable with a ring terminal that is the right size for the wire as well as the bolt it is going to be secured by, at the other end repeat the same process only if your fuse block doesn't use set-screws. If your fuse block uses some sort of set-screw, expose just enough wire to reach the other side of the set-screw. Tighten the screw down and make sure there are no frayed wire strands sticking out which could lead to a short. It is always a good practice to use the terminal covers that come with your amp kit of electrical tape to isolate the terminal and wire crimped inside.
After the fuse block is all secure, it is time to get the wire through the firewall. It may be hard to locate at first but most vehicles will have a factory grommet that can be used as the entrance from under the hood to the interior. Remember, NEVER GO THROUGH THE DOOR JAMB, if you like your car and would like to keep it from being on fire.
Once inside route the wire along factory wiring and down into the kick panel on the side of the car the amplifier will be mounted on. Continue to run the wiring under the vehicle's trim panels until you get to the location of the amplifier. A soft-plastic panel tool can be the saving grace during this process and can be found at most home supply stores.
Step 2 - Remote and Signal Cables
You have your power cable ran, now we have to get the remainder of the wiring from the front back to the amplifier.
Pull your receiver out using the removal keys that were supplied with it, or if it is iso-mounted, remove it the same way the factory radio was removed.
Once the radio is removed from the dash, solder or butt-connect the remote wire for the amplifier with the remote output from the radio, which is usually a blue or blue-white wire. Then plug the RCA Interconnects into the subwoofer output of the head-unit. On some radios with only two sets of RCA outputs, the rears can be switched from rear speaker output to subwoofer output. After making these connections, drop the cables down below the dash and route them to the opposite side of the car that the power wire is in order to reduce the chance of electrical noise from the power cable. Run these RCAs back just like the power cable by hiding them under the trim-panels in the vehicle and only becoming visible near the amp. That is it for this step assuming you have an aftermarket head unit with RCA outputs. If you have a factory stereo then you'll do things differently. First off, make sure your amp has speaker-level inputs and "signal sensing" turn-on capability. If the amp does, you can just tap into the speaker wires behind your stereo, or possibly the rear deck speakers, to get signal to the amp. If it does not have signal sensing then you will have to use a fuse-tap and find an ignition source to run as the remote.
Step 3 - Getting Grounded
Believe it or not, after working in the industry for a few years, I noticed that if a person came into the store with an amp that was acting funky that most times it was because of a bad or corroded ground wire. So consider this the most important step in your installation. You want your ground wire to be as short as possible, but with enough slack to be able to move the amp around if it needs to be removed or changed out for an amplifier with the inputs or outputs on different sides. After locating a grounding position as low as possible to the chassis, and not using a factory bolt, make sure you sand all the paint off of the surface, and if using a longer self-tapping metal screw, be sure that there is no obstacles on the other side of the metal such as brake lines or the fuel tank. After the paint has been sanded off about the size of a nickel to a quarter place a washer on the top of the ground wire's ring terminal and secure the terminal to the vehicle with the metal screw. Make sure it is tight, but also be sure not to strip the hole made by the screw which isn't as hard as you think.
Step 4 - Wiring Up The Speakers
We have power, we have signal, and we have ground. Now all we have left is to hook the speakers up!
Make sure the resistance of your speakers is not lower than what your amplifier is capable of handling, for instance never put a 1-ohm load on an amplifier that is only 2-ohm stable. For more information on Speaker and Subwoofer wiring click HERE.
Now, mount your amp and make your connections. Try to use gentle curves with your wires and cables when possible.
Before you fire up the amp to test, turn the amplifier's gains all the way down. And if you’ve disconnected any connectors relating to the airbag, make sure to reconnect them. You don’t want to trip an error light that’ll need resetting. Now, reconnect your vehicle's negative battery terminal. Verify that the amp turns on when you turn the car on. Then you can play some music and set your gains.
For help on setting your Gains click HERE.
This is a pretty intricate guide, and if followed will yield in a working stereo 9 times out of 10. It is not a guarantee as every vehicle is different. If you have any more questions about your installation, give us a call or send us a chat and we will help as much as we can. We can also not be held liable for any damages that occur to your vehicle while following this guide as it is not concrete and is to be followed as suggestions of good practice.