Balanced and Unbalanced Audio Lines
A description of the pins in certain audio cables (RCA, 1/4" 2 conductor, etc) and their funtions

Pin |
Function |
1 |
Chassis ground (cable shield) |
2 |
positive polarity terminal ("hot") |
3 |
return terminal[2] ("cold") |
Also known as “Cannon Connector” to reflect inventor’s name.
Comes in 3, 4, 5 pin and mini 3 M/F pin configurations.
Most common professional microphone and audio connector.
Some equipment reverses pin 2 (- cold) and pin 3 (+ hot).
Unbalanced Audio: RCA, ¼” 2 conductor, 3.5/2.5 mm 2 conductor.
Traditional unbalanced cables use two lines to transmit the audio signal - a hot line which carries the signal and shield line. This is all that is required to transmit audio and is common in short cables (where noise is less of a problem) and semi-professional applications.
Initial Publish Date: April 7th, 2025
Transcribed by: Tyler Rowe, Customer Service