Above 500 Hz, Bark scale maps logarithmically to frequency change

Evidence

A logarithmic frequency scale is used in part (c) as the abscissa. The straight broken line indicates that a logarithmic relation between criticalband rate and frequency is a very useful approximation for frequencies above 500 Hz. This approximation leads to the relation between increments in Bark (or increments of 100 mel) to a relative frequency change of about 20%. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 940

Categorization

• DEFINE: Captures the log relation operating above 500 Hz where 1 Bark equates to roughly a 20% frequency change.
• QUESTION: Worth recalling this 20%-per-Bark relation when later chapters translate between Bark steps and just-noticeable pitch intervals.