Goniometer (audio)

A goniometer is often included in analog audio equipment to display a Lissajous figure which shows the amount of stereo (that is, phase differences) in a dual-channel signal. It allows the sound technician to adjust for optimal stereo and determine the makeup of errors such as an inverted signal. Many goniometers also provide a VU or PPM as a secondary function. A goniometer adapted for surround metering is called a 'jellyfish display'. This term was coined by DK-Technologies A/S from Denmark.