Amplifier installation kits, or wiring kits usually include all or most of the things you need to install your amp. But you don’t need the full kit if you already have most of what you need; you can go buy whatever you’re missing separately. If starting from nothing, it’s usually a lot cheaper to get a kit. Also make sure the kit you buy includes what you need. For example: most kits only come with one set of RCAs. This is fine for a sub installation, but you will need another pair if you plan on doing 4 speakers on a 4 channel amp.
What’s in the kit?
Amp kits will include the wires, cables, fuse holders, and connectors you need to install your amp. Some include more pieces than others. This 4 gauge Rockford Fosgate amp kit ($75 on Amazon with Prime shipping) includes everything you need to get your system hooked up and sounding good. Cheaper kits can be had, but the wires won’t be true AWG size and not carry current as well as good, name brand kits.
This will be the longer of the two thick wires in your kit. It runs from your battery to your amp.
This will be the shorter of the two thick wires, usually less than 3 feet. This goes from your amp to the chassis or body of your car.
This the long single wire in the kit, usually blue. It runs from a switched 12V source, like the remote turn on wire on the back of aftermarket radios, to your amp.
This is the wire that is actually two wires together. Obviously this goes from your amp to your speakers, one side to positive, one side to negative.
The RCAs are signal cables that run from the output on the back of your head unit, or low level converter (more on that later), to the input on the amp.
This is what protects your car, battery, and amp from getting fried if something goes wrong. This should ALWAYS be installed and as close to the battery as possible, usually no more than 18″.
Various Connectors and Terminals
Most kits will come with wire connectors and terminals so you can connect the wires where they need to go.
How to pick what kit you need
Amp kits are sized by the power and ground wire. For example, if you buy an 8 gauge amp kit, the power and ground wire will be 8 gauge. The speaker wires are usually 16 AWG or less, and the remote wire is usually 18 AWG.
Assuming the kits you are looking at are a good brand with true AWG wire, here’s the basic wire size you need based on your power requirements:
Just match the max amperage or fuse rating on your amp to the amperage on the chart, find out how long your wire is going to be, and you can find out what size wire you need.
If you are ever unsure, or are going with a cheap kit, it is probably best to just jump up a gauge. You can’t go wrong by getting bigger wire (smaller gauge) just don’t ever get smaller than recommended. That can cause the wire to get too hot from trying to pull more current than it’s designed for and possibly cause a fire.