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Binaural Hearing and Human Sound Localization
Jens Blauert, Bochum
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a???e?? (akúin)to hearAcoustics
Physics Psychophysics
sounds sensations
Psychophysics sensations
Physics sounds
acoustic event auditory
event
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Head-Related Coordinate System
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Some Key Words
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Effect of Head Movement
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Binaural Hearing and Human Sound Localization
- Introductory remarks - Directional
hearing in the median sagittal plane -
Directional hearing with sounds from lateral
directions - Distance perception and
inside-the-head locatedness - Summing
localization - Auditory precedence and the
echo threshold - The effect of interaural
decorrelation - Binaural signal detection
- Suppression of reverberance and coloration
- Summary
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Directional Hearing in the Median Sagittal Plane

Directional hearing in the median sagittal plane

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directional bands
boosted bands
1/3 oct noise
Directional Hearing in the Median Plane
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Directional Hearing with Sounds from Lateral
Directions
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ear axis
Lateralization
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attenuators delay lines
Generation of ITDs and ILDs
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Lateralization Blur for ILDs
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Lateralization Due to ILDs
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Lateralization Blur for ITDs
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right ear
left ear
ITD-Lateralization Cues
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Lateralization due to ITDs (broad-band signals)
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Distance Perception Inside-the-Head
Locatedness
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Summing Localization Auditory Precedence
Echoes
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Standard Stereo-Listening Arrangement
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Summing Localization for Broad-Band Sounds
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Ear Signals for Impulsive Sounds in Stereo
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Summing Localization with Sideways Loudspeakers
after Plenge Theile
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primary auditory event
broad- band sounds
echo
Auditory Effects with Two Coherent Sound
Sources Summing localization Precedence
Effect Echo Threshold
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signal running speech of 50 syllables/s
delay of the reflection
Precedence Effect, Haas Effect and Backward
Inhibition
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The Effect of Interaural Decorrelation
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Some Further Key Words
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3 independent noise generators
Controlling the Degree of Coherence
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Spatial Extent of the Auditory Event as a
Function of Interaural Correlation after
Dubrovski Cherniak, 1966
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The Perceptive Phenomena of Auditory
Spaciousness
Pioneer researches e.g., Kuhl, West, Marshall,
Barron, Schroeder, Morimoto
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Binaural Signal Detection Suppression of
Reverberance and Coloration
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The Binaural IntellegibilityLevel Difference,
BILD Cherrys Experiment
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degree of AM, m
reverberant chamber
reverb
threshold of perceptibility
anechoic
Binaural Suppression of Reverberance Danilenkos
Experiment
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Advantages of Binaural Hearing
higher localization accuracy, lower blur better
source segregation (transparency) suppression of
undesired signals (cocktail-party
effect) suppression of coloration and
reverberance (better articulation) gtgt clearer
auditory perspectiveltlt better sense of
envelopment higher auditory source width
(auditory spaciousness) gtgt better spatial
impressionltlt
Higher Quality of the Acoustics!
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Thank You for Your Attention
jens.blauert_at_rub.de www.ruhr-uni-bochum.de/ika
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More details regarding the topic of this lecture
can be found in Jens Blauert (1997) Spatial
Hearing The Psychophysics of Human Sound
Localization published by The MIT Press,
Harvard MA, ISBN 0-262-02413-6
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TASK A Young men and women (about 30 years
old) have applied to be admitted to a school
for airline pilots. For being accepted, they
must have very good spatial-hearing
capabilities. This is necessary, among other
reasons, because they have to respond correctly
to signals from auditory displays in the
cockpit. Outline a battery of perceptual tests
which could be used to evaluate these
capabilities. (a) What would you
measure? (b) Which methods would you
apply? (c) What equipment would you need?
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TASK B The binaural-hearing capabilities of
elderly people (over 65 years) are to be
evaluated by means of routine screening tests.
The goal is to assess their abilities to
localize sounds in space and to communicate
under acoustically adverse conditions. The
information is needed , among other reasons, to
decide if hearings aids should be applied to
them and, if yes, which kind of these?
Outline a battery of perceptual tests that could
be used to evaluate these capabilities. (a)
What would you measure? (b) Which methods
would you apply? (c) What equipment would you
need?