Phonetics - Lesson 7

How is a consonant defined?

• As a letter

• By how it’s shaped by articulators

• By its role in syllable structure

• (By its acoustic and physical properties)

In English, more consonants than vowels in Roman alphabet:

• 14 vowel phonemes - /i, ɪ, e, ɛ, æ, ə, ʌ, ɚ, ɝ, u, ʊ, o, ɔ, ɑ/

• 5 diphthongs - /eɪ, aɪ, oʊ, ɔɪ, aʊ/

• 24 consonant phonemes - /p, b, t, d, k, g, f, v, θ, ð, s, z, ʃ, ʒ, h, t, ʃ, d, ʒ, m, n, ŋ, w, j, l, ɹ/

Consonants vs. Vowels:  How do they differ in terms of production?

• Contrary to vowels, consonants are not produced just by movements of the tongue + lips

• Consonants are produced through vocal tract movements and constrictions that filter/ shape the airflow coming from the lungs then passing through the larynx. 

Consonants vs. Vowels: Sound Sources

Vowels: Sound is produced through vocal fold vibrations, in the larynx.

• Changes in lip rounding and tongue position filter the airstream and affect the vowel sound through changes in resonance in the vocal tract.

Vowels can stand alone and create meaningful utterances (e.g., “oh!” /oʊ/, “I” /aɪ/…)

• Not the case for consonants

Consonants vs. Vowels: Sound Sources

Consonants: Divided into

• Sonorants: like vowels, produced through voicing (=vocal fold vibrations) in the larynx.

• Obstruents: produced through noise created by two articulators at the point of airflow constriction in the oral cavity.

  • For voiceless obstruents (e.g., /p, t, k/), noise created only at the point of constriction.

  • For voiced obstruents, (e.g., /b, d, g/), vocal folds vibrate in addition.

• They differ in their sound sources

Consonants are classified depending on whether they come before, after or in-between a vowel

• Prevocalic Consonant: consonant placed before vowel  “tea” /ti/

• Postvocalic Consonant: consonant placed after vowel  “cat” /kæt/

• Intervocalic Consonant: consonant placed in-between vowels  “okay” /okeɪ/

Vowels are classified in terms of:

• Tongue height (high, mid, low)

• Tongue advancement (front, central, back)

• Lip rounding ((un)rounded))

Consonants are classified in terms of:

• Manner of production

• Place of articulation

• Voicing

Manner of Production

How the airstream is filtered/shaped as it passes through the vocal tract

• E.g. fully obstructed → stop consonants e.g. /d/

• E.g., forcing air through a narrow channel → fricatives e.g., /f/

• Stops (Plosives), Fricatives, Affricates, Nasals, Glides, and Liquids refer to different manners of production

Place of Articulation

Where in the vocal tract is the airstream constriction happening to produce one particular consonant

• This determines the place of articulation

• Which articulators are involved

Place of Articulation Chart

Place of Articulation	Articulators Involves	IPA Consonants
Bilabial	Upper + lower lips	/p, b, m, w/
Labiodental	Lower Lip + Upper Central Incisors	/f, v/
Interdental	Tongue Blade + Teeth	/θ/(teeth), /ð/ (them)
Alveolar	Tongue Blade + Alveolar Ridge	/t, d, s, z, n, l/
Postalveolar	Front of Tongue + Back of Alveolar Ridge	/ʃ/ (ship), /ʒ/ (vision), /tʃ/ (chip), /dʒ/ (jeans), /ɹ/
Palatal	Tongue Blade + Hard Palate	/j/ (yellow)
Velar	Back of Tongue + Velum	/k, g, ŋ, w/
Glottal	Vocal Folds	/h/

Voicing

State of the vocal folds

• Voiced: vocal folds adducted (closed) to create vibration

• Voiceless - vocal folds abducted (open)

• Several obstruents in English work in pairs:

  • Share manner of production and place of articulation, but differ only in voicing.

  • E.g.: /p/ is voiceless while /b/ is voiced

Stop Consonants

Stop consonants are also called plosives

• /p/: pin - /pɪn/

• /t/: top - /tɑp/

• /k/: cut - /kʌt/

• /b/: bat - /bæt/

• /d/: den - /dɛn/

• /g/: gig - /ɡɪɡ/

Characteristics of Stops

Produced by completely obstructing the airstream in the oral cavity

Produced by a full stop of the airstream in the oral cavity before

release of air

• The velum is also raised to avoid air going into the nasal cavity

• Intraoral air pressure builds up behind the closure

The closure is released, producing a burst of air (“plosive”)

3 Characteristics of Stops

• Three places of articulation: bilabial, alveolar, velar

• Three voiceless stops: /p, t, k/

  • Sound source = noise of air released after obstruction of articulators

• Three voiced stops: /b, d, g/

  • Sound sources = vocal folds vibration + noise of air released after obstruction of articulators

Stops (A manner of production)

Summary of place of articulation + Voicing

/p/: voiceless bilabial stop /b/: voiced bilabial stop

/t/: voiceless alveolar stop /d/: voiced alveolar stop

/k/: voiceless velar stop /g/: voiced velar stop

Alveolar tap /ɾ/

Allophones of /t/ and /d/

• Ie. battle, coddle, cutie, latter-ladder

• Production in-between a /t/ and a /d/

• The alveolar tap is the allophone that represents that in-between

• A tapped stop is produced even faster than a stop consonant

• The tap often occurs with intervocalic “t/d” or “t/d” digraph in unstressed syllables, and in words ending in –ity:

  • ‘Be.tter, ‘stu.tter, ‘ma.tted, ‘ba.ttle…

  • Community, divinity, authenticity, sensitivity

Glottal stop /ʔ/

Allophones of /t/ and /d/

• Ie. Button, mountain, Latin...

• Often at the end of words

• More noticeable in British English: e.g., “Li’l bi’” transcribed as / lɪʔl̩ bɪʔ/

• The vocal folds both stop and release the airstream (as in “uh-oh”)

• In American English, in some speakers, occurs in words where /t/ or /nt/ is followed by /n/: button, mountain, Latin /bʌʔn̩/ /maʊnʔn̩/ /læʔn̩/

  • n̩ shows a syllabic consonant

    • Vowels are syllabic because they are the nucleus of a syllable

    • n̩ represents the vowel in that syllable

    • n̩ is the syllable nucleus

• Glottal stop is also found in connected speech:

  • “cat ‘n dog”  /kæʔn̩dɑg/

  • Sittin’  /sɪʔn̩/

• And between vowels of individual words or across words:

  • Hawaii  /həwaɪʔɪ/

  • She eats  /ʃiʔits/