Car Audio Wiring

Car Audio Power Wire

Power wire is one of the most important parts of an amplifier installation. The proper gauge is the second most important consideration, next to fusing. The proper gauge should be used so that the amplifier is not choked off by the size limitations of the wire. If you use too small of a power wire you can get a large voltage drop between the battery and the amplifier. This voltage drop can cause distortion in the output and even cause the amplifier to shut off if it is equipped with under-voltage protection. When selecting a power wire, be sure to purchase one that has many hundreds or thousands of strands so that it will be easier to install and will not break when passing around sharp corners. Also make sure that the jacket of the wire is of a material that will resist chemicals such as oil and battery acid that it will encounter in the engine compartment.
When running power wire always make sure to cover it in protective wire loom in the engine compartment and to use rubber or plastic grommets when passing through any metal or abrasive surface. Otherwise the power wire can chaff and eventually short out.

Car Audio Speaker Wire
Speaker wire is also important in terms of size and strands for the same reasons but the jacket is not as important because it will not see the same chemicals as the power wire. When shopping for speaker wire, look for oxygen free copper (OFC) wiring. The size of your speaker wiring depends on the amount of power going to your speakers and the length of wire from the amplifier to the speakers. Most systems will need to use 16 gauge to 12 gauge wire.

Car Audio Signal Cables
Signal or RCA cables are also important for their noise rejection properties. Cables range in price from a couple of dollars to over one hundred dollars a pair. Most decently priced cables in the twenty to thirty dollar range (for a twenty foot pair) should be adequate for most listeners and noise situations. Twisted pair cables offer much better noise rejection properties as opposed to coaxial cables (the most common). Twisted pair cables consist of two small gauge wires that are twisted around each other in a helix pattern. Coaxial cables are one small gauge wire jacketed by a braided cable which are then both encased in a plastic jacket. The advantage of the twisted pair cables is in the twist in the cables. By twisting the cables noise picked up by one cable will theoretically be canceled by that same noise in the opposite cable. Twisted pair cables can be difficult to find so ask for them specifically when buying RCA cables.

Features and terms that may be encountered with regard to wiring are:
Butt Terminals: This type of terminal resembles a long barrel and is used to connect small gauge wires together. These type are crimp terminals and considered less desirable than soldering when soldering is an option. These terminals are also sometimes referred to as crimp connectors though that term can apply to many variations of crimp terminal.

Deep Cycle: A battery usually reserved for marine use that can be drained and replenished many times. While popular years ago many installers have relegated this battery to system use only with a traditional car battery for main power.

Farad (F): The base unit of measure for capacitor storage. One farad is very larger and is equivalent to one million microfarads (uF).

Gauge: This refers to the diameter of the wire. The smaller the number, the larger the wire. Sixteen is common for speaker wire, eight is common for average size amplifiers, while four gauge and below is used for large amplifiers. For reference, four gauge wire is about the same diameter as the average male pinky finger.

Gel Cell: A type of battery that uses a gel type acid. These batteries can be desirable because they may be mounted upside down without the danger a standard type battery would pose.

Heat Shrink Tubing: A type of insulating plastic that resembles a drinking straw. A small portion of this tube is cut off and placed on a wire before soldering. After the connection is soldered and cooled, the tube is slid over the joint and shrunk around the wires by means of a heat gun or hot hair dryer.

Microfarads (uF): The more common unit used to measure capacitor storage. One million microfarads is equivalent to one Farad.

OFC: An abbreviation for oxygen free copper. This is the most desirable wire to buy and there is really no reason to buy any other kind. As the name implies it is pure copper that is free from oxygen impurities.

Spade Terminals: A type of terminal used on most speakers. The type found on speakers are male spades while the ones used to connect to these terminals are female spades. These terminals are also referred to as quick disconnects though this name can apply to many different types of terminals that come apart quickly.

Voltage Rating: Referring to the amount of voltage a capacitor is rated to handle. The very least a capacitor used for reinforcement should be rated at is 16 volts while 20 volts is much more desirable and available on the slightly more expensive capacitors.