Physical stimuli map to separate hearing sensations only within audible physical ranges

Evidence

The most important physical magnitude for psychoacoustics is the time function of sound pressure. The stimulus can be described by physical means in terms of sound pressure level, frequency, duration and so on. The physical magnitudes mentioned are correlated with the psychophysical magnitudes loudness, pitch, and subjective duration, which are called hearing sensations. … Physical stimuli only lead to hearing sensations if their physical magnitudes lie within the range relevant for the hearing organ. For example, frequencys below 20 Hz and above about 20 kHz dot not lead to a hearing sensation whatever their stimulus magnitude. … A major goal of psychoacoustics is to arrive at sensation magnitudes analogous to stimulus magnitudes. For example, we can state that a I-kHz tone with 20 mPa sound pressure produces a loudness of 4 sone in terms of hearing sensation. The unit “sone” is used for the hearing sensation loudness, in just the same way as the unit “Pa” is used for the sound pressure. It is most important not to mix up stimulus magnitudes such as “Pa” or “dB” and sensation magnitudes such as “sone”. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 123

Categorization

• DEFINE: Introduces the core psychoacoustic framework: stimulus magnitudes (Pa, dB) versus hearing sensations (loudness, pitch), with ‘sone’ as the sensation unit for loudness — foundational vocabulary for this whole book.