Closely spaced tones sum by sound pressure to peak loudness
Evidence
For small frequency separations up to about 10 Hz, the hearing system is able to follow the beats between the two tones that lead to a loudness sensation corresponding to the peak value reached within the beating. The peak corresponds to twice the sound pressure of the single tone, and leads to a loudness level of 66 phon. This means that for narrow frequency separations, the loudness level is determined by the peak value of the sound pressure reached within the beating period. In order to estimate the loudness level of such a two-tone complex, we have to add the sound pressures of the two tones. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1207
Categorization
Category: Causal Relationships
- DEFINE: Explains the mechanism by which the ear follows envelope beats when tones are close in frequency.
Related
- Widely separated tones add by loudness, not pressure or intensity (similarity 0.90)
- Medium-separated tones add by intensity once the ear stops tracking envelope (similarity 0.88)
- Intermediate separations cause loudness to follow intensity addition instead of pressure addition. (similarity 0.86)
- Perceived loudness of concurrent tones hinges on frequency separation via three distinct mechanisms (similarity 0.84)
- Two tones within a critical band interact to reduce total loudness (similarity 0.83)
- Ear sensitivity depends jointly on frequency and on sound level (similarity 0.82)
- Two tones fuse into one unless their separation exceeds critical bandwidth (similarity 0.82)
- Loudness depends on frequency, angle, duration, and envelope, not just level (similarity 0.81)
- Hearing resolves close tones through beats, rough fusion, then separation bands (similarity 0.80)
- Loudness perception requires a tenfold intensity increase to double (similarity 0.80)
- Perceived loudness of time-varying sounds is set by short-time peak values. (similarity 0.80)
- Loudness perception shows distinct behavior in two critical-band-defined regions (similarity 0.80)
- Loudness at high sound levels arises from excitation spreading across adjacent frequency bands (similarity 0.80)
- Two close sine tones produce amplitude beats at their frequency difference (similarity 0.79)
- Suppressor tones reveal tuning curves matching neural frequency selectivity (similarity 0.79)