On the relation between pitch and level.

Area of Science:

• Auditory Perception
• Psychoacoustics
• Acoustic Phonetics

Background:

• Pitch is the perceived highness or lowness of a sound, typically linked to waveform periodicity.
• Previous research suggests a subtle influence of sound level on perceived pitch.
• The current study aimed to confirm genuine pitch changes, distinct from procedural artifacts.

Purpose of the Study:

• To systematically investigate and confirm the relationship between sound level and perceived pitch.
• To differentiate genuine pitch shifts from potential confounds in auditory experiments.
• To assess the impact of musical training on level-dependent pitch perception.

Main Methods:

• Conducted systematic pitch matching tasks using pure and complex tones at varying sound levels.
• Employed interval matching tasks to corroborate pitch shift observations.
• Compared pitch perception accuracy and level-dependent shifts between musicians and non-musicians.

Main Results:

• Confirmed that the pitch of low-frequency pure tones decreases with increasing sound level by over half a semitone.
• Observed that complex tones did not exhibit this pitch shift.
• Demonstrated that pitch shifts are anti-symmetric and transitive, consistent with pitch perception.
• Noted smaller, but directionally similar, shifts in interval matching tasks.
• Found musicians to be more precise but exhibit similar average pitch shifts as non-musicians.

Conclusions:

• The perceived pitch of low-frequency pure tones is weakly but systematically dependent on sound level.
• These findings present a challenge to existing theories of pitch perception.
• The effect is robust across different tasks and participant groups, though precision varies.