What’s the Difference Between Balanced and Unbalanced? This question is a common one in the world of audio equipment, and the answer can have a significant impact on the quality of your sound. In this article, we’ll delve into the details of balanced and unbalanced cables and signals, their uses, and how they affect your audio experience.
Unbalanced Cables and Signals
Unbalanced cables consist of two connectors with two conductors each, connected by two wires inside the cable—a signal wire and a ground wire. These cables are typically used for connecting a guitar to an amp or for AV components.
The signal wire is usually in the center of the cable, with the ground wire surrounding it. This ground wire serves two functions—it carries part of the audio signal and shields the main signal wire from outside interference, such as hum from lights and transformers, and RF (radio frequency) interference from TV and radio transmissions.
However, unbalanced cables are not very good at suppressing noise from outside interference. As a result, they should have a maximum length of 15-20 feet (4-6 meters), especially when used in noisy environments and with signals that are low level to begin with.
Balanced Cables and Signals
In contrast to unbalanced cables, a balanced cable has three conductors in the connector and three wires in the cable: two signals’ wires plus a separate ground wire. The ground wire still surrounds the signal wires and is used as a shield against interference, but the gear utilizes the extra signal wire in a special way.
Balanced cables use two signal wires; both carry a copy of the signal, but the two copies are sent with their polarity reversed. This polarity reversal is what makes a balanced cable special. When the receiving gear flips the inverted signal back into its original orientation, the noise picked up by the cable is cancelled out, leaving only the original signal.
Because of this noise cancellation, balanced cables can support much longer cable runs; 50 to 100 feet (15-30 meters) is not uncommon. They are typically used for microphones, and the interconnect cables between consoles, signal processors, and amps in a pro sound system or recording studio environment.
Using the Right Cable for the Right Signal
It’s important to note that using a balanced cable on an unbalanced signal gives you no benefits. The jacks on the gear on both ends of the cable must be designed for balanced signals as well; otherwise, there’s no circuitry to do the polarity inversion that produces the noise cancellation.
On the other hand, using an unbalanced cable with gear that expects balanced signals will work, but the signal will be unbalanced and susceptible to the same noise as any unbalanced signals. Therefore, it’s crucial to check the documentation of your gear or the labels on the gear itself to determine what type of signal a given jack is designed to support.
In conclusion, the choice between balanced and unbalanced cables and signals depends on your specific audio needs. Unbalanced cables are simpler and cheaper, but they are more susceptible to noise and have a shorter effective range. Balanced cables, on the other hand, offer superior noise rejection and can be used over longer distances, but they require compatible equipment and are more expensive. By understanding these differences, you can make an informed decision and optimize your audio setup for the best possible sound.