Chorus effect

In music, a chorus effect (sometimes chorusing or chorused effect) occurs when individual sounds with approximately the same timbre, and very similar pitch converge and are perceived as one. While similar sounds coming from multiple sources can occur naturally, as in the case of a choir or string orchestra, it can also be simulated using an electronic effects unit or signal processing device.

Methods

When the effect is produced successfully, none of the constituent sounds are perceived as being out of tune. It is characteristic of sounds with a rich, shimmering quality that would be absent if the sound came from a single source. The effect is more apparent when listening to sounds that sustain for longer periods of time.

The chorus effect is especially easy to hear when listening to a choir or string ensemble. A choir has multiple people singing each part (alto, tenor, etc.). A string ensemble has multiple violinists and possibly multiples of other stringed instruments.

In spite of the name, most electronic chorus effects do not accurately emulate this acoustic ensemble effect. Instead, they create a constantly moving electronic shimmer.