Quantization always injects noise that lowers audio signal-to-noise ratio

Evidence

Although the quantizer will pick the output level that causes minimum error, there will on average always be some error. This error adds noise and distortion to the signal and is often referred to as quantization noise. Ideally this noise should be random and often dither is added to ensure this. The effect of the error is to reduce the signal to noise ratio of the audio signal. If a binary word of Nbits bits is used to encode the audio signal, then the maximum signal to noise ratio is given by: For a 16-bit word (the CD standard), this gives a maximum signal to noise ratio of 96 dB. — David Howard, Jamie Angus, coustics and Psychoacoustics, 2651

Categorization

• DEFINE: Defines quantization noise and its cause — the error from approximating continuous values with discrete levels.
• corroborated: 4 independent passages support this claim — David Howard, Jamie Angus, coustics and Psychoacoustics, 2651
• XREF: connects to: Shaping quantization noise to sit 13 dB below the signal renders it inaudible; Uniform quantization noise requires about 60 dB signal-to-noise to stay masked; Non-uniform quantizer spacing exploits masking and signal statistics to cut noise (+7 more)

Broader Connections

• Non-uniform quantizer spacing exploits masking and signal statistics to cut noise #corroborates (0.85)
• Audio compression exploits masking to discard inaudible signal parts #qualifies (0.85) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 2020
• Uniform quantization noise requires about 60 dB signal-to-noise to stay masked #qualifies (0.82)
• Internal listener noise rises steeply as signal-to-noise ratio worsens #expands (0.80) — Dijk, Pim van, Physiology, Psychoacoustics and…, 5624
• Noise-vocoding degrades speech by replacing detail with band-limited noise envelopes. #exemplifies (0.78)
• Noise suppression algorithms can degrade speech quality in non-stationary noise #exemplifies (0.75) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 2452