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Quantisation noise

Definition

The distortion introduced when a continuous audio signal is rounded to discrete digital values. Lossy codecs concentrate quantisation noise at predictable frequency bands determined by the codec's psychoacoustic model and the target bitrate.

Related terms

Double compression
The condition in which a video has been encoded at least twice through a lossy codec. The term is also used loosely...
MEMS microphone
A Micro-Electro-Mechanical Systems microphone: the capsule type used in virtually all modern smartphones and tablets. MEMS microphones have a characteristically flat midrange...
Psychoacoustic masking model
The perceptual model used by lossy codecs such as MP3 and AAC to decide which frequency components can be discarded or coarsely...
Self-noise (noise floor)
The electrical noise inherent in a microphone circuit and capsule, measured in dB(A) equivalent input noise. Different microphone types have characteristic noise...
Spectral fingerprint
The characteristic frequency response profile of a recording device, including roll-off curves, resonance peaks, and self-noise level. Comparing a recording's spectral fingerprint...

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