quantization Assigning a series of discrete numerical values to an analog waveform. In digital audio, the analog waveform’s amplitude is converted to a number (quantized) each time a sample is taken.

quantization error Difference between the actual analog value and the number representing that analog value. Quantization error occurs when the analog value falls between two quantization steps; the quantizer assigns the closest number. Quantization error introduces noise and distortion in digital audio, often heard as a roughness at low signal levels, particularly during reverberation decay.

quantization word length The number of bits created by the A/D converter at each sample point. Compact Disc records quantization words 16 bits in length.