Introduction to Acoustics

Psychoacoust
13. Psychoacoustics
Psychoacoustics is concerned with the relationships
between the physical characteristics of sounds and
their perceptual attributes. This chapter describes:
the absolute sensitivity of the auditory system for
detecting weak sounds and how that sensitivity
varies with frequency; the frequency selectivity
of the auditory system (the ability to resolve or
hear out the sinusoidal components in a complex
sound) and its characterization in terms of an array
of auditory filters; the processes that influence the
masking of one sound by another; the range of
sound levels that can be processed by the auditory
system; the perception and modeling of loudness;
level discrimination; the temporal resolution of
the auditory system (the ability to detect changes
over time); the perception and modeling of pitch
forpureandcomplextones;theperception
of timbre for steady and time-varying sounds;
the perception of space and sound localization;
and the mechanisms underlying auditory scene
analysis that allow the construction of percepts
corresponding to individual sounds sources when
listening to complex mixtures of sounds.
13.1 Absolute Thresholds............................. 460
13.2 Frequency Selectivity and Masking ........ 461
13.2.1 The Concept of the Auditory Filter 462
13.2.2 Psychophysical Tuning Curves ..... 462
13.2.3 The Notched-Noise Method ........ 463
13.2.4 Masking Patterns
and Excitation Patterns.............. 464
13.2.5 Forward Masking....................... 465
13.2.6 Hearing Out Partials
in Complex Tones ...................... 467
13.3 Loudness ............................................ 468
13.3.1 Loudness Level
and Equal-Loudness Contours .... 468
13.3.2 The Scaling of Loudness ............. 469
13.3.3 Neural Coding
andModelingofLoudness......... 469
13.3.4 The Effect of Bandwidth
on Loudness ............................. 470
13.3.5 Intensity Discrimination............. 472
13.4 Temporal Processing
in the Auditory System ......................... 473
13.4.1 Temporal Resolution Based
on Within-Channel Processes ..... 473
13.4.2 Modeling Temporal Resolution.... 474
13.4.3 A Modulation Filter Bank? .......... 475
13.4.4 Duration Discrimination ............. 476
13.4.5 Temporal Analysis Based
on Across-Channel Processes ...... 476
13.5 Pitch Perception .................................. 477
13.5.1 Theories of Pitch Perception ....... 477
13.5.2 The Perception of the Pitch
of Pure Tones............................ 478
13.5.3 The Perception of the Pitch
of Complex Tones ...................... 480
13.6 Timbre Perception ............................... 483
13.6.1 Time-Invariant Patterns
and Timbre............................... 483
13.6.2 Time-Varying Patterns and
Auditory Object Identification ..... 483
13.7 The Localization of Sounds ................... 484
13.7.1 Binaural Cues ........................... 484
13.7.2 The Role of the Pinna and Torso.. 485
13.7.3 The Precedence Effect ................ 485
13.8 Auditory Scene Analysis ........................ 485
13.8.1 Information Used to Separate
Auditory Objects........................ 486
13.8.2 The Perception of Sequences
of Sounds................................. 489
13.8.3 General Principles
of Perceptual Organization ......... 492
13.9 Further Reading
and Supplementary Materials ............... 494
References .................................................. 495
459
Part D 13