Balanced Line Signal Cable

In telecommunications and professional audio a balanced line or balanced signal pair is a transmission line consisting of two conductors of the same type each of which have equal impedances along their lengths and equal impedances to ground and to other circuits.

Balanced line signal cable.

One of the signal wires gets inverted which allows the cable to completely avoid picking up outside interference. The two wires form a circuit carrying the audio signal one wire is in phase with respect to the source signal. A balanced cable by contrast has three conductors in the connector and three wires in the cable. The chief advantage of the balanced line format is good rejection of external noise when fed to a differential amplifier.

Two of those wires carry the signal while one carries the ground. As in the unbalanced cable the ground wire still surrounds the signal wires and is used as a shield against interference. Two signals wires plus a separate ground wire. Common forms of balanced line are twin lead used for radio frequency signals and twisted pair used for lower f.

A typical balanced cable contains two identical wires which are twisted together and then wrapped with a third conductor foil or braid that acts as a shield. Balanced cables and signals a balanced cable by contrast has three conductors in the connector and three wires in the cable. Balanced cables vs unbalanced cables. But what makes a balanced cable special is the way the gear utilizes that extra signal wire.

Two signals wires plus a separate ground wire.