Volume changes alter perceived frequency balance, not just loudness
Evidence
The phon scale is a subjective scale of loudness based on the judgments of listeners to match the loudness of tones to reference tones at 1 kHz. The curve for N phones intersects 1 kHz at N dB(SPL) by definition, and it can be seen that the relative shape of the phon curves flattens out at higher sound levels, as shown in Figure 2.13. The relative loudness of different frequencies is not preserved, and therefore the perceived frequency balance of sound varies as the listening level is altered. This is an effect we have all heard when the volume of a recording is turned down and the bass and treble components appear suppressed relative to the midrange frequencies, and the sound becomes “duller” and “thinner.” — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 626 (
#corroborates, via linked claim)
Categorization
- corroborated: 2 independent passages support this claim
- XREF: connects to: Perceived pitch shifts measurably with loudness in frequency-dependent directions — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 921; Small bass-level changes strongly alter perceived spectral balance; Tactile vibration raises perceived loudness and lowers preferred bass levels — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1826 (+3 more)
Broader Connections
- Turning down volume suppresses perceived bass and treble relative to midrange
#corroborates(0.95) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 626 - Loudness changes shift perceived pitch; reverb conceals the effect musically
#expands(0.82)