Interconnects

Speaker wire is used to make the electrical connection between loudspeakers and audio amplifiers. Modern speaker wire consists of two or more electrical conductors individually insulated by plastic (such as PVC, PE or Teflon) or, less commonly, rubber. The two wires are electrically identical, but are marked to identify the correct audio signal polarity. Most commonly, speaker wire comes in the form of zip cord.

The effect of speaker wire upon the signal it carries has been a much-debated topic in the audiophile and high fidelity worlds. The accuracy of many advertising claims on these points has been disputed by expert engineers who emphasize that simple electrical resistance is by far the most important characteristic of speaker wire.

Early speaker cable was typically stranded copper wire, insulated with cloth tape, waxed paper or rubber. For portable applications, common lampcord was used, twisted in pairs for mechanical reasons. Cables were often soldered in place at one end. Other terminations were binding posts, terminal strips, and spade lugs for crimp connections. Two-conductor ¼-inch tip-sleeve phone jacks came into use in the 1920s and '30s as convenient terminations.

Some early speaker cable designs featured another pair of wires for rectified direct current to supply electrical power for an electromagnet in the loudspeaker. Essentially all speakers manufactured now use permanent magnets, a practice which displaced field electromagnet speakers in the 1940s and 1950s.

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