Article Notes #2: William A. Yost and Psychoacoustics of human sound and perception by Robert A. Lutfi and Christopher A. Brown

You can access the original paper here.

• The three primary qualities of perceiving sound are pitch, timbre, and loudness.
• Pitch is closely attached to the sound source.
• Loudness varies with distance from the source.
• Timbre is affected by room acoustics, how the source is supported, and how it’s driven to vibrate.

• Pitch is minor subject to extraneous factors.
• It depends more on the properties of the resonating source itself.
• Sounds that are most significant to use are mainly periodic. These sounds have a harmonic structure.

• Pitch helps us to segregate sound sources perceptually.
• Pitch affects the meaning of a spoken sentence through prosody, the emotional state of the speaker, and their gender.
• We segregate complex sounds based on pitch.

• Individual fibers in the auditory system are selective to different frequencies.
• Regarding the temporal features, our auditory system provides a synchronous response of the nerve fibers to the signals.

• Masked threshold: we can mask a tone using white noise.
• Sound source perception as the primary function of hearing (because it’s key to our survival).
• Sound source localization arises from our ability to process relatively small differences in auditory signals between two ears.
• We use ITD and ILD as cues to localize sound sources in the horizontal place.
• Cocktail party problem (Cherry — 1953).

• The maximum number of spatially separated sound sources in an auditory scene that we’re able to process is four.
• For five or more sources, accuracy changed and the listener tended to use the overall level to perform the loudness difference task rather than individual source levels (this indicated the inability to “hear out” individual sources on streams).
• Sound source localization isn’t a purely psychoacoustic phenomenon but rather based on an integration from several systems (auditory, visual, and vestibular).