Читать книгу Engineering Acoustics - Malcolm J. Crocker - Страница 149

Figure 4.5 presents the auditory field for an average, normal young person who has not suffered any hearing loss or damage. The lower curve represents the hearing threshold, that is, the quietest audible sound at any frequency. The upper curve represents the discomfort threshold, that is, the sound pressure level at any frequency at which there is a sensation of discomfort and even pain in the ears. Speech is mainly in the frequency range of about 250–6000 Hz and at sound pressure levels between about 30–80 dB at 1–2 m (depending upon frequency). Of course, the sound pressure level of speech can approach 90 dB at about 0.2–0.3 m from someone if they are shouting loudly. The sound of vowels is mostly in the low‐frequency range from about 250 to 1000 Hz, while the sound of consonants is mainly in the higher frequency range of about 1000–6000 Hz. Music is spread over a somewhat greater frequency range and a greater dynamic range than speech. (The dynamic range represents the difference in levels between the lowest and highest sound pressure levels experienced.)

Figure 4.5 Human auditory field envelope.