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The Plan for Today• There’s a DSP exercise for you to work on!
• Due next Thursday.
• Also: I have posted a couple of readings on TOBI (an intonation transcription system) to the course website.
• Let’s get into it by reminding ourselves a little bit about how F0 can be meaningfully manipulated in language.
• Does anybody remember what the following things are?
1. Lexical tones
2. Pitch accents
3. Stress
Intonation• Languages superimpose pitch contours on top of word-based stress or tone distinctions.
• This is called intonation.
• It turns out that English:
• has word-based stress
• and phrase-based pitch accents (intonation)
• The pitch accents are pragmatically specified, rather than lexically specified.
• = they change according to discourse context.
English Intonation• We’ll analyze English intonation with a framework called TOBI
• Tones and Break Indices
• Note: intonational patterns vary across dialects
• The patterns and examples presented today might not match up with your own intonational system
• Also: this framework has only been applied to a few (primarily western) languages
• There’s more info at
• http://www.ling.ohio-state.edu/~tobi/
• Course in Phonetics, pp. 124-128
Levels of Prominence• In English, pitch accents align with stressed syllables.
• Example: “exploitation”
vowel X X X X
full vowel X X X
stress X X
pitch accent X
• Normally, the accent falls on the last stressed syllable.
• (This is called the nuclear accent.)
Pitch Accent Types• In English, pitch accents can be either high or low
• H* or L*
• Examples: High (H*) Low (L*)
Yes. Yes?
H* L*
Magnification. Magnification?
• As with tones in tone languages, “high” and “low” pitch accents are defined relative to a speaker’s pitch range.
• My pitch range: H* = 155 Hz L* = 100 Hz
• Mary Beckman: H* = 260 Hz L* = 130 Hz
Whole Utterances• The same pitch pattern can apply to an entire sentence:
H*
H*: Manny came with Anna.
L*
L*: Manny came with Anna?
H*
H*: Marianna made the marmalade.
L*
L*: Marianna made the marmalade?
Information• Note that there’s a tendency to accent new information in the discourse.
• 4 different patterns for 4 different contexts:
H*
H*: Manny came with Anna.
H*
H*: Manny came with Anna.
L*
L*: Manny came with Anna?
L*
L*: Manny came with Anna?
Pitch Tracking• H* is usually associated with a peak in F0;
• L* is usually associated with a valley (trough) in F0
• Pitch tracking can help with the identification of pitch peaks and valleys.
• Note: it’s easier to analyze utterances with lots of sonorants.
• Check out both productions of “Manny came with Anna” in Praat.
• Note that there is more to the intonation contour than just pitch peaks and valleys
• The H* is followed by a falling pitch pattern
• The L* is followed by a rising pitch pattern
Tone Types• There are actually three types of tones at play, but
we’ll start with just two:
1. Pitch Accents
• associated with a stressed syllable
• may be either High (H) or Low (L)
• marked with a *
2. Boundary Tones
• appear at the end of a phrase
• not associated with a particular syllable
• may be either High (H) or Low (L)
• marked with a %
Phrases• Intonation organizes utterances into phrases
• “chunks”
• Boundary tones mark the end of intonational phrases
• Intonational phrases are the largest phrases
• In the transcription of intonation, phrase boundaries are marked with Break Indices
• Hence, TOBI: Tones and Break Indices
• Break Indices are denoted by numbers
• 1 = break between words
• 4 = break between intonational phrases
Question Formation• Note that not all questions end in L* H%.
• What’s the intonational difference between these two?
Did you see Bob?
L*H%
Where did you go?
H* L%
• The upsloping intonation only applies to yes/no questions.
• Also note: “Uptalk”
• = application of L* H% pattern to declarative sentences.
0 Level Boundaries• 0 level boundaries are marked wherever there is clear coarticulation across a word boundary
• Also for flaps across word boundaries, as in “got it”
0 1 1 4
More Tones• Note that there can be more than one pitch accent within an intonational phrase.
• Examples:
Anna gave Manny a mango.
L* H* L%
Anna gave Manny a mango.
H* H* H* L%
• The last accent in a phrase is somehow more prominent than the others.
• This accent is called the nuclear accent.
Downstepping• Successive H* accents tend to drift downward in F0 within an intonational phrase.
• = downdrift, or downstepping
• This provides further evidence for phrasal organization.
• Downstepping essentially reduces the pitch range.
• Downstepped H* accents are denoted with a !H*
• Anna gave Manny a mango.
H* !H* !H* L%
• There’s a lovely, yellowish, old one.
H* !H* !H* L%
Intermediate Phrases• A downstepping pattern can be reset by the presence of an intermediate phrase boundary.
• Example:
It’s lovely, and yellowish, and it’s an old one.
H* !H* L- H* L-L%
• Intermediate phrase boundaries are marked with a break index of 3.
• At the end of each intermediate phrase is an phrase accent
• Either Low (L-) or High (H-)
One Phrase vs. Two Phrases• No intermediate phrase boundary:
“I” means insert.
H* H*L-L%
1 1 4
• An intermediate phrase boundary, with a L- phrase accent:
“I” means insert.
H* L- H*L-L%
3 1 4
One Phrase vs. Two Phrases• No intermediate phrase boundary:
Marianna made the marmalade.
L* L* H-H%
1 1 1 4
• An intermediate phrase boundary, with a H- phrase accent:
Marianna made the marmalade.
L* H- L* H-H%
3 1 1 4
Filling the Gap• Another feature of phrase accents is that they fill in the gap between the nuclear accent and the boundary of the intermediate phrase.
L* + H L- H%
1 0 1 1 4
Combinations• Different combinations of phrase accents and boundary
tones have different connotations.
1. L-L% Declarative sentences
2. H-H% Yes/No questions (usually)
3. L-H% Continuations
4. H-L% A “plateau” pattern
• Upstep: boundary tones after H- are higher than normal.
A Chunking Reviewutterance
intonational phrase (intonational phrase) ...
intermediate phrase (intermediate phrase) ...
(pitch accent) nuclear accent
(stressed syllable) stressed syllable
Break Indices• 4 marks boundaries between intonational phrases
• associated with a boundary tone (H% or L%)
• sense of complete disjuncture
• 3 marks boundaries between intermediate phrases
• associated with a phrase accent (H- or L-)
• lesser sense of disjuncture
• 1 marks boundaries between words
• 0 marks non-boundaries between words
• (2 marks uncertainties or apparent mismatches)
• rarely used
Bitonal Pitch Accents• In addition to H* and L*, there are two bitonal pitch accents
• L + H*
• L* + H
• The starred element denotes the tone which is associated with the stressed syllable
• L + H* = high peak on stressed syllable, preceded by a sharp rise in pitch
• L* + H = low pitch target on stressed syllable, followed by a sharp rise in pitch
More Downstepping• Bitonal pitch accents can also undergo downstepping.
L + H* L + !H* L + !H* L-L%
1 1 1 1 1 4
Pitch-Accents Round-up• There are four pitch accents:
• H*
• L*
• L + H*
• L* + H
• They attach to stressed syllables
• The final pitch accent in an intonational phrase is the nuclear accent.
• Generally perceived as more prominent.
Deep Thought Questions• What might happen if:
• The shortest period checked is longer than the fundamental period?
• AND two fundamental periods fit inside a window?
• Potential Problem #1: Pitch Halving
• The pitch tracker thinks the fundamental period is twice as long as it is in reality.
• It estimates F0 to be half of its actual value
More Deep Thoughts• What might happen if:
• The shortest period checked is less than half of the fundamental period?
• AND the second half of the fundamental cycle is very similar to the first?
• Potential Problem #2: Pitch doubling
• The pitch tracker thinks the fundamental period is half as long as it actually is.
• It estimates the F0 to be twice as high as it is in reality.
Microperturbations• Another problem:
• Speech waveforms are partly shaped by the type of segment being produced.
• Pitch tracking can become erratic at the juncture of two segments.
• In particular:
• voiced to voiceless segments
• sonorants to obstruents
• These discontinuities in F0 are known as microperturbations.
• Also: transitions between modal and creaky voicing tend to be problematic.
Back to Language• F0 is important because it can be used by languages to signal differences in meaning.
• Note:
• Acoustic = Fundamental Frequency
• Perceptual = Pitch
• Linguistic = Tone
A Typology• F0 is generally used in three different ways in language:
1. Tone languages (Chinese, Navajo, Igbo)
• Lexically determined tone on every syllable
• “Syllable-based” tone languages
2. Accentual languages (Japanese, Swedish)
• The location of an accent in a particular word is lexically marked.
• “Word-based” tone languages
3. Stress languages (English, Russian)
• It’s complicated.
Mandarin Tone
ma1: mother
ma2: hemp
ma3: horse
ma4: to scold
• Mandarin (Chinese) is a classic example of a tone language.
How to Transcribe Tone• Tones are defined by the pattern they make through a speaker’s frequency range.
• The frequency range is usually assumed to encompass five levels (1-5).
• (although this can vary, depending on the language)
1
2
3
4
5Highest F0
Lowest F0
• In Mandarin, tones span a frequency range of 1-5
• Each tone is denoted by its (numerical) path through the frequency range
• Each syllable can also be labeled with a tone number (e.g., ma1, ma2, ma3, ma4)
Tone
1
2
3
4
How to Transcribe Tone• Tone is relative
• i.e., not absolute
• Each speaker has a unique frequency range. For example:
1
2
3
4
5Highest F0
Lowest F0
Female
Male
100 Hz
200 Hz 350 Hz
150 Hz
General Relativity• In ordinary conversation, for European languages (Fant, 1956) :
• Men have an average F0 of 120 Hz
• A range of 50-250 Hz
• Women have an average F0 of 220 Hz
• A range of 120-480 Hz
• Children have an average F0 of 330 Hz
• In a normal utterance, the F0 range is usually one octave.
• i.e., highest F0 = 2 * lowest F0
Relativity, in Reality• The same tones may be denoted by completely different frequencies, depending on the speaker.
• Tone is an abstract linguistic unit.
female speaker
male speaker
ma, tone 1 (55)
Accent Languages• In accent languages, there is only one pitch accent associated with each word.
• The pitch accent is realized on only one syllable in the word.
• The other syllables in the word can have no accent.
• Accent is lexically determined, so there can be minimal pairs.
• Japanese is a pitch accent language…
• for some, but not all, words
• for some, but not all, dialects
Japanese• Japanese words have one High accent
• it attaches to one “mora” in the word
• A mora = a vowel, or a consonant following a vowel, within a syllable.
• For example:
• [ni] ‘two’ has one mora.
• [san] ‘three’ has two morae.
• The first mora, if not accented, has a Low F0.
• Morae following the accent have Low F0.
It’s actually slightly more complicated than this; for more info, see: http://sp.cis.iwate-u.ac.jp/sp/lesson/j/doc/accent.html
Stress Languages• Stress is a suprasegmental property that applies to whole syllables.
• It is defined by more than just differences in F0.
• Stressed syllables are higher in pitch (usually)
• Stressed syllables are longer (usually)
• Stressed syllables are louder (usually)
• Stressed syllables reflect more phonetic effort.
• More aspiration, less coarticulation in stressed syllables.
• Vowels often reduce to schwa in unstressed syllables.
• The combination of these factors give stressed syllables more prominence than unstressed syllables.