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Phonetics COMD2338Taylor
•Vowel production
•Introduction to sound waves
How many vowel sounds are there in US English?Between 11 and 13, depending on your
dialectDoes not include diphthongsEx: Beat, bit, bait, bet, bat, but, bother,
boot, book, boat, bawdy, body
Describing vowels
Difficult to use tongue position as a descriptorHigh-low/front-back should not be viewed as
absolute descriptions of tongue positions
Vowel chart reflects frequencies; i.e., how one vowel sounds relative to the others
No distinct boundaries between vowels
[i][u]
[o]
[ɑ][æ]
[ʌ]
http://www.uiowa.edu/~acadtech/phonetics/
Sound waves: Why describe sounds in terms of their physical nature?Helps speech pathologists understand
how sounds can be confusedFor vowels, in particular, articulatory
gestures are not very good descriptionsRecordingsSpeech synthesis
What is sound?
Sound: a disturbance of (air) molecules by some kind of movementThese disturbances are called sound wavesSound waves cause molecules to move back
and forth, bumping into one anotherEventually this disturbance travels to your ear,
causing your ear drum to vibrateYour brain perceives this as sound
How do sound waves work?
Sound waves can differ inpitchqualityloudness
They spread like ripples in a pond. . .Voiced sounds: large, regular pulsesVoiceless sounds: smaller, irregular
pulses
Speech sounds
Speech sounds are created when a sound passes through the vocal tractThis sound resonates at different frequenciesThe frequencies at which this sound resonates
are called formants
Linguists have two ways to visually represent speech sounds: waveforms and spectrograms
Terminology
Frequency: how fast the sound wave travelsMeasured in terms of Hertz (cycles per
second)Think in terms of pitch
Amplitude: how big of a disturbance the wave makesMeasured in terms of decibelsThink in terms of loudness
Sound properties of vowels
Complex acoustic structureNumber of different frequencies
simultaneouslypitch (auditory property)
fundamental frequency (acoustic measure)• pulses/second: 100Hz = 100 pulses/second
you can hear F0 by using creaky voice
added frequencies from resonanceyou can hear these by whispering/whistling
Spectrograms
A spectrogram is an illustration of time, frequency, and amplitudeTime: horizontal axisFrequency: vertical
axisAmplitude: how dark
the bars areEach dark bar
represents a vowel formant
How to describe English vowel soundsParameters (in order)
1. Height
2. Frontness
3. Rounding
4. Tenseness (if applicable)
DiphthongsDialect issues
All vowels (canonical)
AmEngl Vowel Chart (Canonical Placement)
beat [i] boot [u]
bit [ɪ] father [ɚ] book [ʊ]
bait [e] sofa [ə] boat [o]
bet [ɛ] but [ʌ] caught [ɔ]
bat [æ] father [a] cot [ɑ]
Beware: There is considerable variation in English.
Some vowel mnemonics
English height (descending):front: 'green mints may melt fast'back: 'nude cooks wrote bawdy logs'
English lip rounding:green vs nudemint vs cookmay vs wrotemelt vs bawdy
Central Vowels in English
[ə] and [ʌ] are both considered “mid central unrounded vowels”, and the tense/lax distinction is not applicable.
[ʌ] is used in stressed syllables and stressed one-syllable words:cup, rug, above
[ə] is used in unstressed syllables, unstressed one-syllable words like ‘the’ [ðə]: sofa, above, the house
Use [ɚ] for unstressed syllables ending in [ɹ]:father
Moving from one V to another
Involves changing the auditory quality of the vowelaccomplished by moving the tongue and
changing the shape of the chamberdifficult to describe exactly how your tongue is
movingmay not move the same way twicedoes not move the same way in different
contexts
Diphthongs
The nucleus is usually (although not always) the first V of the pair [oʊ], [aʊ], [aɪ], [eɪ], [ɔɪ]
The nucleus is more prominent than the off-glide or the on-glideOff/on-glide is often very short
Exception: [ju] in English
Sometimes transcribed as a glide (consonant)
Diphthongs
A diphthong is a combination of vowels. The tongue moves from one vowel position (i.e. “target”) to another.
The final segment of a diphthong is often written as an ‘off-glide’ approximant
English diphthongs:[aɪ] or [aj] pie, rye, lied[aʊ] or [aw] cow, how, round[ɔɪ] or [ɔj] boy, coin, boil[oʊ] or [ow] cold [eɪ] or [ej] say(also: [ij], [uw]) keel, mood
American English diphthongs
[eɪ] ‘bait’, ‘gate’[aɪ] ‘bite’, ‘kite’[oʊ]‘boat’, ‘goat’ [ɔɪ] ‘boy’, ‘coy’[aʊ]‘pow’, ‘cow’[ju] ‘cute’, ‘use’[uw] ‘boo’[ij] ‘key’
Regional dialects: some examples
‘cot/caught’final [ɚ] to [ə]; [aɹ] to [a]; [ɔɹ] to [ɔ][aɪ] to [a] (monophthongization)
‘guy’[i]–[ɪ] rotation ‘beat’ ‘bit’[æ] to [iə] ‘candle’