Choosing the right wire

The type of in-wall wire and cables you use will depend on what kind of signal you need to carry, where you're going to route the wire, and how far the signal will have to travel to go between your gear. Whatever type of wire you choose, be sure to get one that's rated for in-wall use by the Underwriters Laboratory (UL). This is normally denoted with a CL2 or CL3 rating for speaker wire and audio/video cables. Many Ethernet cables are rated for in-wall use, denoted with a CM, CMR, or CMP rating. The UL looks at heat generated from current flowing through wire, how quickly the cable will catch and spread fire when exposed to flame, and the wire's susceptibility to damage from external stresses.

Also look for cable that's rated for your specific scenario. For example, you'll want cable rated CL2P or CL3P if you're placing it in heating ducts, and you'll want cable rated for direct burial if you're running it through the ground to outdoor speakers. Also, be sure to check your local building and fire code and buy wire accordingly.

Speaker wire
There are two main factors to consider with speaker cable: the gauge and the number of conductors.

The gauge of your wire should depend on how far the wire has to travel from the receiver to the speaker. The lower the American Wire Gauge (AWG) number, the thicker the wire. Significant power losses can occur over long runs, resulting in lower performance. While this probably won't be a problem in most single-room setups, it could be an issue for multi-room systems. Use the chart below as a guideline for wire gauge selection.

Two-conductor wire (A) is used when running wire directly to a speaker, while 4-conductor wire (B) is often used for runs to volume controls.

You can choose speaker cable with two or four conductors (see photo at right). Two-conductor cable is all you need to wire one speaker. Four-conductor wire is mostly used in multi-room applications with volume controls (it may also be used with stereo-input speakers). For example, if you're going to run wire from a receiver in your living room to a pair of speakers with a volume control in your dining room, you would run four-conductor wire from the receiver to the volume control, and two-conductor wire from the volume control to each speaker. (Of course, if you don't have four-conductor wire, you could also use two two-conductor wires.)

You may see in-wall speaker cable identified in short hand that indicates its gauge and its number of conductors. For example:

• 16/2 is 16-gauge wire with 2 conductors
• 14/4 is 14-gauge wire with 4 conductors

Terminating speaker wire
You have two different options for terminating speaker wire: bare wire or speaker connectors. While some folks prefer bare wire as the purest connection, we generally don't recommend it for in-wall installations because of the risk of short circuits and corrosion.

For good, solid connections, use speaker wire terminated with connectors instead of using stripped bare wire ends. There are a variety of speaker connectors available but the most commonly used are pin and banana connectors. You can find connectors that either twist or crimp on to your stripped speaker wire.

If you do decide to hook up your wire without connectors, use a wire stripper to take about 3/8-inch of insulation off the ends of each lead, exposing bare wire strands (be careful not to cut these strands). Twist each lead's bare wire strands tightly, so no stray strands are sticking out. Loose strands could make contact with the cable's other lead and cause a short circuit, potentially damaging your gear. A complete discussion of speaker connectors and terminals can be found in our speaker glossary.

Ethernet cable (CAT-5, -5e, -6)
There are a number of uses for Ethernet cable — like creating a wired computer network, or carrying audio/video and control signals in a whole-house system. This family of cables is often referred to as CAT-5, but these days, you'll likely be installing CAT-5e or CAT-6. These newer cables are able to pass more data, and send that data at a faster rate. CAT-5e and CAT-6 products are backwards compatible with devices designed to work with CAT-5 cable.

The benefits of using Ethernet cable to pass audio/video signals
The use of Ethernet cable for whole-house audio/video systems is growing more popular. Ethernet cables stand up to interference better than speaker or audio/video cables, even the common unshielded variety, called "UTP" (unshielded twisted pair). Running long lengths of Ethernet cable can also be more cost-effective than running long lengths of audio/video cable.

There are a few multi-room music and video systems that use Ethernet cable, plus separate devices that you can use with regular audio/video gear called "baluns". These devices allow you to send regular audio/video signals to a different room via Ethernet cable.

Terminating Ethernet cables
Since lengths of Ethernet cable will vary depending on the size of your home and how many rooms you're running wire to, you'll probably be terminating your own Ethernet cables. You'll need RJ-45 connectors for the ends of the cable, and a crimp tool to secure the connection.

When terminating the cables, you'll need to strip the Ethernet cable, and untwist the twisted pairs so that you can insert each conductor into the proper hole in the RJ-45 connector. You'll most likely use the common 568b configuration which places the cables in this order:

• Pin 1 — white/orange wire
• Pin 2 — orange wire
• Pin 3 — white/green wire
• Pin 4 — blue wire
• Pin 5 — white/blue wire
• Pin 6 — green wire
• Pin 7 — white/brown wire
• Pin 8 — brown wire

Audio/video cables
Some setups require you to run audio and video cables through your walls. Whether you're working on a single-room system, like running cables from a ceiling-mounted projector to a rack of A/V equipment, or wiring your home for audio and video in every room, there are a couple things to keep in mind.

Long runs of audio/video cable are susceptible to interference, and also tend to be relatively expensive. That's part of why Ethernet cable has become a more popular option.

If you do want long runs of audio/video cables, we recommend using RG-6 cable when possible — it's HD-capable and far less expensive than HDMI.

Terminating audio/video cables
If you do use long runs of audio/video cable, chances are you'll need to terminate it yourself. (It is worth noting, however, that digital A/V cables will come pre-terminated, so you'll only need to terminate analog cables.) The difficulty of terminating A/V cable will vary depending on the connectors you use. Some require you to strip the cable and crimp on the connector, while others simply twist on to the end of the cable. If you're running multiple cables, it can be helpful to use labels or colored bands to tell the different cables apart.