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9.35 Sensation And Perception
Spring 2009
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Auditory Scene Analysis
Kimo Johnson
April 23, 2009
Tuesday, April 28, 2009
Auditory scene analysis
•
•
Tuesday, April 28, 2009
Source segregation
-
Spatial separation
Spectral and temporal qualities
Stream segregation
-
proximity: frequency or time
continuity: follow trajectory
similarity: frequency, timbre, intensity
symmetry and closure
Harmonic overtones
2f
1.6f
1f
Segregation of fusion
Synchrony of onsets
1f
Fusion
2f
Segregation
Harmonic intensities
Single sound organization
Figure by MIT OpenCourseWare.
adapted from Handel figure 7.2
Tuesday, April 28, 2009
Old-plus-new heuristic
Figures removed due to copyright restrictions.
Tuesday, April 28, 2009
Auditory stream
Figures removed due to copyright restrictions.
Tuesday, April 28, 2009
Stream segregation
•
•
•
•
Tuesday, April 28, 2009
Proximity
Continuity
Similarity
Symmetry and closure
Frequency
Multiple sounds
Time
Figure by MIT OpenCourseWare.
adapted from Handel figure 7.4
Tuesday, April 28, 2009
Multiple sound organization
•
•
Tuesday, April 28, 2009
Tone sequences
-
Vary parameters to cause perception of
subsequences
Conflicting organizations
-
Ambiguous sequences that put strategies in
conflict
Proximity
Figure by MIT OpenCourseWare.
Tuesday, April 28, 2009
Results
Frequency separation
(semitones)
15
10
5
0
0
50
100
150
200
Tone repetition time
(m sec)
Figure by MIT OpenCourseWare.
from van Noorden, 1975
Tuesday, April 28, 2009
J.S. Bach
•
Tuesday, April 28, 2009
Toccata and Fugue in D Minor ~1700
J.S. Bach
•
Toccata and Fugue in D Minor ~1700
(c)
#
#
#
Figure by MIT OpenCourseWare.
Tuesday, April 28, 2009
Similarity
•
Tuesday, April 28, 2009
Sounds are grouped by timbre
Similarity
•
Sounds are grouped by timbre
Example
from Music, Cognition, and Computerized Sound, ed. Perry Cook
Tuesday, April 28, 2009
Competing organizations
Frequency
A
B
C
Time
Figure by MIT OpenCourseWare.
Bregman and Pinker, 1978
Tuesday, April 28, 2009
Scale illusion
•
Deutsch, 1975
Part 2
Part 1
L
R L
R L
R L
R L
R L
R L
L R
L
R
R L
R L
R L
R L
R
L
L R
R
R L
Figure by MIT OpenCourseWare.
Tuesday, April 28, 2009
Scale illusion
•
Deutsch, 1975
Part 2
Part 1
L
R L
R L
R L
R L
R L
R L
L R
L
R
R L
R L
R L
R L
R
L
L R
R
R L
Figure by MIT OpenCourseWare.
Demo
Tuesday, April 28, 2009
Scale illusion
•
Deutsch, 1975
Part 2
Part 1
L
R L
R L
R L
R L
R L
R L
L R
L
R
R L
R L
R L
R L
R
L
L R
R
R L
Figure by MIT OpenCourseWare.
Part 3
Demo
Figure by MIT OpenCourseWare.
Tuesday, April 28, 2009
Frequency
Continuity
Noise
Sound
Noise
Time
Time
Figure by MIT OpenCourseWare.
Kluender and Jenison 1992 - glides
Tuesday, April 28, 2009
Continuity
adapted from Bregman, 1990
Tuesday, April 28, 2009
Continuity
adapted from Bregman, 1990
Tuesday, April 28, 2009
Restoration
•
•
Tuesday, April 28, 2009
Sasaki (1980) - familiar piano melodies
Warren and Sherman (1974)
-
the *eel fell off the car
The *eal fell off the table
Frequency Graphs
Figures removed due to copyright restrictions.
Tuesday, April 28, 2009
Melodies
Diana Deutsch, 1972
Tuesday, April 28, 2009
Melodies
Diana Deutsch, 1972
melody 1
Tuesday, April 28, 2009
Melodies
Diana Deutsch, 1972
melody 1
melody 2
Tuesday, April 28, 2009
Music
Tuesday, April 28, 2009
Music
guitar and sax
Tuesday, April 28, 2009
Music and Speech
Perception
Kimo Johnson
April 29, 2008
Tuesday, April 28, 2009
Linguistic universals
•
•
•
•
•
Discreteness
Semanticity
Arbitrariness
Openness
Duality of patterning
Hockett, 1963
Tuesday, April 28, 2009
Music grammars
•
•
•
•
•
Tuesday, April 28, 2009
Discreteness: N pitches per octave
Semanticity: scales, chords, keys
Arbitrariness
Openness
Duality
Octave
•
•
Frequency ratio 2:1
•
First overtone is 2 : 1
Tuesday, April 28, 2009
Greatest number of identical
overtones
Sensory dissonance
Sensory dissonance
"Roughness"
"Two tones"
"Beats"
12-tet scale steps:
Octave
Fourth frequency
Fifth interval
Figure by MIT OpenCourseWare.
Plomp and Levelt, 1965
Tuesday, April 28, 2009
Local consonance
12-tet scale steps
m3
M3 fourth
fifth
M6
Octave
Sensory dissonance
Unison
6/5 5/4
4/3
3/2
5/3
Frequency ratio
2/1
Amplitude
1/1
Frequency
Figure by MIT OpenCourseWare.
Sethares, 1993
Tuesday, April 28, 2009
Pythagorean comma
C C!
f1
=
fi
=
3
f0
2
3
f i −1
2
B
C!
B"
D
A
E"
G!
E
G
F!
Tuesday, April 28, 2009
F
Pythagorean comma
C C!
f1
=
fi
=
3
f0
2
3
f i −1
2
B
C!
B"
D
A
E"
G!
! "12
3
2
12
3
219
Tuesday, April 28, 2009
E
7
≈ 2
≈ 1.0136
G
F!
F
Pythagorean tuning
C C# D
1/ 256/ 9/
1 243 8
Eb E
32/ 81/
27 64
F F# G G# A Bb B
4/ 729/ 3/ 128/ 27/ 16/ 243/
3 512 2 81 16 9 128
C : E = 81/64 = 1.2656
C : E = 5/4 = 1.25
C : Eb = 32/27 = 1.1852
C : Eb = 6/5 = 1.20
C# : F# = 1.3515 ≠ 1.333
Tuesday, April 28, 2009
Pythagorean tuning
C C# D
1/ 256/ 9/
1 243 8
Eb E
32/ 81/
27 64
F F# G G# A Bb B
4/ 729/ 3/ 128/ 27/ 16/ 243/
3 512 2 81 16 9 128
C : E = 81/64 = 1.2656
C : E = 5/4 = 1.25
C : Eb = 32/27 = 1.1852
C : Eb = 6/5 = 1.20
C# : F# = 1.3515 ≠ 1.333
Tuesday, April 28, 2009
wolf
Other tuning systems
•
•
•
•
Tuesday, April 28, 2009
Just diatonic
Meantone (1400)
Well-temperaments
- Werckmeister (1645-1706)
- Young (1773-1829)
Equal temperament (~1900)
Optimal well-temperament
Tempering of major triad
16
14
12
OWT2
10
8
6
4
2
Eb
OWT1
Y2
W3
Bb
F
C
G
D
A
E
B
F#
C# G#
Major triad
Figure by MIT OpenCourseWare.
Polansky et. al, 2008
Tuesday, April 28, 2009