Terhardt, E. (1992). The SPINC function for scaling of frequency in auditory models. Acustica 77, 40-42
Essentially, three types of auditory frequency scale can be distinguished: (a) The mel scale; (b) the critical-band scale; and (c) the SPINC scale. The latter is based on the just noticeable frequency difference for pure tones (JND of frequency, or Spectral Pitch INCrement). It is shown that, quantitatively, the three types of scale are significantly different. For economically scaling frequency in systems for the processing of audio-signals the SPINC scale is shown to be optimal. A formal description of the SPINC scale is derived from a number of experimental data on the JND of frequency.