Intermediate separations cause loudness to follow intensity addition instead of pressure addition.
Evidence
For larger frequency distances between the two tones, i.e. in the range of 20 Hz up to about 160 Hz, the equally loud tone is constant in level and matches at about 63 dB. This corresponds to an addition of the sound intensities. In other words, in that region of frequency separation in which the ear no longer takes into account the temporal variation of the envelope of the sound pressure, the sound intensity is the value that creates loudness. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1208
Categorization
Category: Causal Relationships
Related
- Medium-separated tones add by intensity once the ear stops tracking envelope (similarity 0.93)
- Widely separated tones add by loudness, not pressure or intensity (similarity 0.89)
- Closely spaced tones sum by sound pressure to peak loudness (similarity 0.86)
- Ear sensitivity depends jointly on frequency and on sound level (similarity 0.85)
- Loudness perception requires a tenfold intensity increase to double (similarity 0.85)
- Two tones within a critical band interact to reduce total loudness (similarity 0.85)
- Loudness at high sound levels arises from excitation spreading across adjacent frequency bands (similarity 0.84)
- Loudness grows as a power law of intensity, not linearly. (similarity 0.84)
- Loudness growth with intensity requires experimental quantification, not intuition (similarity 0.84)
- Perceived loudness depends on frequency content and duration, not just sound pressure level (similarity 0.84)
- Two tones fuse into one unless their separation exceeds critical bandwidth (similarity 0.84)
- Loudness perception shows distinct behavior in two critical-band-defined regions (similarity 0.84)
- Sound power and intensity levels are unaffected by source correlation, unlike pressure level (similarity 0.84)
- Loudness grows when sound energy spills beyond a single critical band (similarity 0.84)
- Loudness is the summed specific loudness across critical-band rates, not the raw spectral level (similarity 0.84)
Broader Connections
- Sound power and intensity levels are unaffected by source correlation, unlike pressure level
#expands(0.85) — David Howard, Jamie Angus, coustics and Psychoacoustics, 258