Lectures Five and Six Orienting Question

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Lectures Five and Six - Orienting Question
How does the way individuals produce sound lead
to acoustic-phonetic variability?
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(No Transcript)
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Sawtooth waveform
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A sinusoid at the same frequency as the sawtooth
fits reasonably to the sawtooth.
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Addition of two sinusoids to approximate the
sawtooth.
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Addition of six and an infinite number of
sinusoids to approximate the sawtooth better.
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Amplitude spectrum of sawtooth. Axes are
frequency (x) and amplitude (y).
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Frequency response of vocal tract for vowel /i./.
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Frequency response of vocal tract for vowel /ae/.
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Formant track calculated using hqanal overlaid
on spectrogram. Subject Sergio. Phrase Well
well will them.
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Interrogative and declarative forms appear to
have some relation that would be difficult to
capture by phrase structural rules
INTERROGATIVE What book is the boy reading?
DECLARATIVE The boy is reading a book
Transformational rules operate on phrase
structures to give new phrase structures
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Take the example The boy is reading what book
Art N Auxiliary verb Verb Interrogative
adjective Noun NP NP VP New type of VP
Slight extension of our phrase structural rules
to incorporate interrogative adjectives would
deal with this DECLARATIVE sentence.
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To get the interrogative form - use WH-fronting
transformational rule WHAT BOOK THE BOY IS
READING 0 O WHOLE Then use AUX-inversion
transformation to invert "the boy" and "is"
WHAT BOOK IS THE BOY 0 READING 0
Transformational grammars reveal the connection
between related sentences. Would not apply to
phrase structure grammars so they are criticised
by TG.
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Question whether perceive sentences like this
PASSIVE SENTENCES (REQUIRE TRANSFORMATIONS)
SHOULD TAKE LONGER TO PROCESS THAN ACTIVE
SENTENCES THAT DO NOT. Active The boy watered
the flowers Passive The flowers were watered by
the boy Slobin - no differences in processing
times. We are able to understand sentences that
are illegal - by-pass syntax and use semantics.
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• Phoneme definition minimal contrastive unit.
• Occurs in free distribution.
• Plosives - place
• Voicing
• Vowels - tongue position - height
• - front/back
• - all voiced
• Voicing controls flow of air from lungs
• Action of vocal cords
• Peel open, snap together
• Sawtooth pulses enter vocal tract
• Sounds like a buzz

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Speech representation in terms of its frequency
content Sinusoids, frequency, amplitude,
phase Low frequency, takes a long time to
repeat High frequency, takes a short time to
repeat Sawtooth is not a sinusoid Can represent
in these terms see diagram slides from
lecture Spectra show what frequencies go into
the vocal tract Next consider how does vocal
tract shape affect these input
frequencies? (Note other forms of excitation,
like voiceless, have different forms of
spectrum, but treatment is similar.)
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Way vocal tract filters individual
frequency Transfer function How to combine to
determine speech output How spectrum propagates
over time, explanation of the spectrogram Adding
a consonant
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Acoustic phonetic variability 1. Segmentation 2.
Definition of coarticulation (influence of one
segment on another) Sequencing Coarticulation
proper - extent - forward/backward Distinguishi
ng sequencing and coarticulation - volitional -
language specific coarticulation Perceptual role
of coarticulation, upcoming words Henke model of
coarticulation Also look at lecture 7 (section on
action theory)
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3. Rate -vowel undershoot 4. Perturbation/compen
sation - Riordan (lips) - Bite block Houde and
Jordan (acoustic) 5. Speaker differences -
Source effects - Filter effects Leiberman
modelling work with articulatory synthesizer
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References Ladefoged, P. (1975). A course in
Phonetics. New York Harcourt Brace
Jovanovich. Rosen, S., Howell, P. (1991).
Signals and Systems for Speech and Hearing.
London and San Diego Academic Press.