Unit 3 outline
-
Upload
amber-trujillo -
Category
Documents
-
view
41 -
download
1
description
Transcript of Unit 3 outline
SPPA 403 Speech Science 1
Unit 3 outline
• The Vocal Tract (VT)• Source-Filter Theory
of Speech Production• Capturing Speech
Dynamics• The Vowels• The Diphthongs• The Glides• The Liquids
SPPA 403 Speech Science 2
Articulation: Lecture Outline
• Brief anatomy review
• Introduction to Source-Filter Theory
• Introduction to tube acoustics
SPPA 403 Speech Science 3
Supraglottal (Articulatory) system
• Comprised of– Cavities– Articulators
SPPA 403 Speech Science 4
Supraglottal Cavities?
SPPA 403 Speech Science 5
• Oral
• Nasal
• Pharyngeal
• (Buccal)-cavity between the teeth and cheek
Supraglottal Cavities
SPPA 403 Speech Science 6
nasal cavity
oral cavity
pharyngealcavity
SPPA 403 Speech Science 7
The vocal tract
SPPA 403 Speech Science 8
Immobile articulators?
SPPA 403 Speech Science 9
Immobile articulators
• Hard palate
• Teeth
SPPA 403 Speech Science 10
Hard Palate
SPPA 403 Speech Science 11
Teeth
SPPA 403 Speech Science 12
Mobile articulators?
SPPA 403 Speech Science 13
Mobile articulators
• Pharyngeal walls
• Soft Palate
• Mandible
• Tongue
• Face, lips and cheeks
SPPA 403 Speech Science 14
Pharyngeal walls
SPPA 403 Speech Science 15
Soft palate
SPPA 403 Speech Science 16
Mandible
SPPA 403 Speech Science 17
Tongue
SPPA 403 Speech Science 18
Face, lips and cheeks
SPPA 403 Speech Science 19
The vocal tract
SPPA 403 Speech Science 20
Unit 3 outline
• The Vocal Tract (VT)• Source-Filter Theory of Speech
Production• Capturing Speech Dynamics• The Vowels• The Diphthongs• The Glides• The Liquids
SPPA 403 Speech Science 21
Simplifying the vocal tract into “tubes” and “valves”
SPPA 403 Speech Science 22
Simplifying the vocal tract into “tubes” and “valves”
SPPA 403 Speech Science 23
The “tube” and “valve” analogy
• Tubes…– Act as an acoustic resonator or filter
• Valves…– Open and close the vocal tract to some tubes
• velopharyngeal port• Oral articulator approximations
– Serve as sound source• Larynx (glottal spectrum)• Within the vocal tract (i.e. /s/)
SPPA 403 Speech Science 24
Source-filter theory of speech production
• The sounds we hear as speech is a function of– Sound source– Vocal tract filtering
• source and the filter are independent of each other
SPPA 403 Speech Science 25
Source-filter theory simplified
SPPA 403 Speech Science 26
Name that vowel!
Same source, different filters
SPPA 403 Speech Science 27
“Larynx? We don’t need no stinking larynx…”
SPPA 403 Speech Science 28
Source characteristics
• The source – does not have to be the larynx– does not have to be periodic
SPPA 403 Speech Science 29
Passing white noise through the filter
SPPA 403 Speech Science 30
Passing white noise through the filter
SPPA 403 Speech Science 31
Same source, different filters
SPPA 403 Speech Science 32
Vocal tract as a tube
SPPA 403 Speech Science 33
Vocal tract as a tube
• Tubes have physical characteristics
• Tubes are acoustic resonators
• Acoustic resonators have frequency response curves (FRC)
• Physical characteristics dictate FRC
SPPA 403 Speech Science 34
Note
• Frequency response curve is also termed the transfer function
SPPA 403 Speech Science 35
Frequency response curve (FRC)
• FRC peaks – resonant or formant frequency
• Resonators have an infinite number of formants
• F1, F2, F3 … denotes formants from low to high frequency
F1 F2 F3 F4
SPPA 403 Speech Science 36
Vocal tract as a tube (Figure 9-1)
Vocal tract: bent tube, closed at one end, with differing Cross-sectional diameter.
Straight tube, closed at one end,of differing cross-sectionaldiameter
Straight tube, closed at one end,with a uniform cross-sectionaldiameter
SPPA 403 Speech Science 37
Characteristics affecting filter properties
• Length.
• Cross-sectional area along its length.
• Whether it is closed at either or both ends.
SPPA 403 Speech Science 38
Area function of a tube
…
Are
a (c
m2)
Length along tube (cm)
SPPA 403 Speech Science 39
Area function of a tube
• Area function dictates the frequency response curve for that tube
Are
a (c
m2)
Length along tube (cm)
SPPA 403 Speech Science 40
Uniform tube (unchanging area function) closed at one end
• First resonance or formant
F1 = c/4l
Where
c=speed of sound (35,000 cm/sec)
l = length of the tube
SPPA 403 Speech Science 41
Uniform tube closed at one end
• Higher resonant frequencies or formants are odd multiples of F1
For example,
• F1 = (c/4l )*1
• F2 = (c/4l )*3
• F3 = (c/4l )*5
SPPA 403 Speech Science 42
Tube example
SPPA 403 Speech Science 43
What about the vocal tract?
• The vocal tract is fairly uniform in its cross-sectional diameter for neutral or central vowel (schwa)
SPPA 403 Speech Science 44
Male vocal tract
Average length 17.5 cm
F1 = (35000/4(17.5))*1 = 1*35000/70 = 500 Hz
F2 = (35000/4(17.5))*3 = 1500 Hz
F3 = (35000/4(17.5))*5= 2500 Hz
SPPA 403 Speech Science 45
Female vocal tract
Average length 14 cm
F1 = (34000/4(14))*1 = 1*35000/56 = 607 Hz
F2 = (35000/4(14))*3 = 1821 Hz
F3 = (35000/4(14))*5= 3035 Hz
SPPA 403 Speech Science 46
Male-female comparison
SPPA 403 Speech Science 47
Articulation in the context of source-filter theory
• neutral vocal tract configuration is an example of an articulatory configuration
• Articulation systematically changes– the filter properties of the vocal tract– the type of sound source