Speaker wire gauge is a critical factor in the audio performance of a system. The speaker wire gauges determines how much electrical power reaches your speaker. If the gauge of the speaker wire is too thin, the wire will have high resistance to the passage of electricity through it.
High resistance to the passage of electricity result in a voltage drop along the wire. As a result, the amplifier can sends electrical power through the speaker wire, however, the speaker wire will prevent that power from reaching the speaker drivers. This reduction in the power that reaches the speakers will result in a decrease in audio quality.
How to Choose the Right Speaker Wire
The speaker wire gauge must be matched to an number of factors related to the speakers and the audio system that uses those speakers. The length of the wire run is one such factor. The longer the run of speaker wire, the more resistance that will develops within the wire.
As a result, the gauge of the speaker wire have to be thicker to prevent the power from dropping along the length of the wire. The impedance of the speakers is another factor. Impedance is measured in units of ohm.
Speakers with a low impedance require a thicker gauge of speaker wire. For example, a speaker with an impedance of four ohms require a thicker gauge of speaker wire than one with an impedance of eight ohms. Eight ohms is a standard impedance for speakers.
Speakers with this impedance can use thinner gauge of speaker wire if the length of the wire run is short. However, if the wire run is long, the gauge of the wire has to be thick to prevent a voltage drop along the length of the wire. The material of the speaker wire is another significant factor in the performance of the wire.
Speaker wire with oxygen-free copper is a high-quality material. The resistance of the oxygen-free copper to oxidation ensure that the wire will carry the electrical current well over the years. Pure copper is another reliable material for speaker wire.
This material is less conductive than oxygen-free copper, however, it is less expensive. Copper-clad aluminum is an even less conductive material. It is the cheapest material for speaker wire.
However, it is prone to corrosion at the connection point of the wire with the speakers. This corrosion will cause poor electrical contact at the connection points. As a result, you should of avoid this material for speaker wire installation that are to be permanent installations.
Select the correct speaker wire gauge for your specific room layout and speaker type. For bookshelf speakers that are only six feet from the receiver, sixteen AWG speaker wire will work. For floor-standing speakers that are thirty feet from the receiver, use at least fourteen AWG speaker wire.
In a theater setup, the front speakers will need a thicker gauge wire than the surround speakers because the surround speakers have a shorter wire run. If you are routing the speaker wire inside a wall, use CL2-rated speaker wire to meet fire safety code. If you are routing the speaker wire outdoors, use UV-resistant speaker wire that can stand up to sunlight exposure.
How you connect the speaker wire to the audio equipment is also important. Using bare wire connections is cheap but oxidizes over time, creating poor sound quality. Using banana plug allows for a secure connection to the audio equipment.
Gold-plated banana plugs are the best because they do not corrode. Another common connection is using spade connector. These offer a large area of contact between the speaker wire and the audio equipment.
If the connections are poor, you may experience audio dropouts or hissing sound. There are some common mistake to avoid when setting up the speaker wire. Do not use a thin speaker wire gauge for the speaker wire if your speaker placement is going to require a long run of wire.
Using a thin gauge wire will starve your speakers of the electrical power they need to produce sound. Flipping the polarity of your speaker wire is another mistake to avoid. It will make the speaker cones vibrate in the opposite direction and reduce the bass of your speakers.
Do not use copper-clad aluminum speaker wire for in-wall speaker installation because it is difficult to replace the installation if anything goes wrong. Following these guidelines will allow your speaker wire to maximize the capacity of your audio equipment.