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Definition

Dither is a type of intentional variation (noise) which is added to a digital audio signal to avoid distortion caused by quantization errors.

Dithering in audio

Dither is often used when an analog signal is being quantized into a finite number of digital levels. It is also often used when a digital signal is being quantized into a fewer number of bits per sample corresponding to a fewer number of digital levels.

Dither randomizes the errors ...