Balanced Line Signal Cable

As in the unbalanced cable the ground wire still surrounds the signal wires and is used as a shield against interference.

Balanced line signal cable.

As in the unbalanced cable the ground wire still surrounds the signal wires and is used as a shield against interference. The two wires form a circuit carrying the audio signal one wire is in phase with respect to the source signal. Common forms of balanced line are twin lead used for radio frequency signals and twisted pair used for lower f. 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.

Two signals wires plus a separate ground wire. The other wire is reversed in polarity. Balanced cables have three conductors and three wires. Two of those wires carry the signal while one carries the ground.

One of the signal wires gets inverted which allows the cable to completely avoid picking up outside interference. 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. 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.