Definition: When you're buying audio cables, chances are you'll see the word "balanced" mentioned often. Balanced audio connectors work on a very simple electrical principle with one goal in mind: the transmission of audio without introduced noise, and with the ability to cancel any noise brought into the line.
Balanced cables have three wires traveling through them; one positive, one negative, and one "ground". What happens through these lines is very smart: while your original signal is being transmitted, it's assumed that any noise problems you may have will be present in both lines; on the receiving end, they're recombined from the original positive and negative signals, and due to phase cancellation, the noise will be eliminated because it's thought of as being out-of-phase with itself. Pretty cool, right?
This makes it easy to run large amounts of cable without noise problems, which you'll usually get with unbalanced connectors.
Balanced cables have three wires traveling through them; one positive, one negative, and one "ground". What happens through these lines is very smart: while your original signal is being transmitted, it's assumed that any noise problems you may have will be present in both lines; on the receiving end, they're recombined from the original positive and negative signals, and due to phase cancellation, the noise will be eliminated because it's thought of as being out-of-phase with itself. Pretty cool, right?
This makes it easy to run large amounts of cable without noise problems, which you'll usually get with unbalanced connectors.
Examples:
XLR and TRS (tip/ring/sleeve) connections are considered balanced.