This article talks about the various types of sound and security wire available today. Sound and security wire is most commonly purchased as a stranded copper product.
These types of wires are manufactured with a riser or plenum rating. Riser, which is commonly referred to as CMR, uses a PVC construction. Plenum, called CMP, can be used in plenum applications. PVC is more cost effective than plenum rated sound and security cables but can’t always be used in the same areas of commerical and residential structures.
For example, a plenum rated product is required in a drop ceiling because the plenum rated wire will not produce a toxic smoke when burned unlike the PVC product. If you plan on running your sound and security wiring through air ducts, you should use a plenum product which will be printed CMP on the wire. The PVC rated product will be printed CMR.
The most common sizes of these products are from 12 AWG to 22 AWG. 16 and 18 AWG are the most widely used, but depending on your exact needs, larger and smaller sizes are stocked at most electrical wholesalers. These circuit sized cables are considered low voltage in the wire and cable word meaning 300 volts or less is required in your application.
These wires are at least 2 conductors but can range much higher. The most common conductor count is 2 because that is what most sound systems require. They are also available in with pairs such as 2 PR, 4 PR and 6 PR. These are less common but are available as normal stocking items.
Sound and security wires can come with or without a shield. The shield is typically an aluminum mylar shield with a drain wire attached to the shield allowing the installer to terminate the electromagnetic noise the shield captures. Shields can be critical to the installer if the there is a fear of any interference to the signal. The shield will increase the price of the wire by 10-20%. While most speaker wires do not require shields, an alarm or security system will utilize a shielded product due to the critical nature of the data being transmitted.
Sound and security wires are some of the most common in today’s copper wiring market. They are extremely versatile in both size and conductor count. Their basic make-up and high demand also means they are very affordable to most installers on bulk reels.