Larynx and Consonant Voicing

Respiration and the Larynx

• Speech sounds are usually produced through the egressive pulmonic airstream which involves air moving out of the lungs.
• Airflow is obstructed in some way to make speech sounds, these obstructions in the vocal tract are called strictures.
• Strictures can occur in the larynx.
• Inside the larynx are two thick flaps of muscle called vocal folds (vocal cords).
• Vocal folds can be moved apart or together, the opening between them is the glottis.
• Vocal folds have four recognizable states, see pages 22-24, figures 10-13 for more information.
• Subglottal pressure (air pressure below the vocal folds) can be varied in intensity, frequency and quality, more information can be found on page 25.

Voicing and Other Variables in Consonants

• Voiceless sounds occur when the vocal folds are spread apart, allowing air to pass unimpeded.
• Voiced sounds occur when the vocal folds are drawn together, and air repeatedly pushes them apart, causing vibration.
• Some phoneticians classify consonants by force of articulation, calling voiceless sounds fortis (strong) and voiced sounds lenis (weak).
• This method of classifying consonants is difficult to prove because the force of articulation is hard to measure/define.
• Place of articulation refers to where the airflow is obstructed.
• Possible places of articulation include bilabial, labiodental, dental, alveolar, post-alveolar, palatal, velar, and glottal.
• Manner of articulation refers to how the airflow is obstructed.
• Possible manners of articulation include plosive, fricative, affricate, nasal, lateral approximant, and approximant.
• Refer to Table 1 on page 52 for the complete chart of English consonants.

Plosives

• Plosive sounds have four phases of articulation:
• Closing Phase: The articulators move to form a total stricture (no air escapes).
• Compression Phase: Air is compressed as it is stopped from escaping.
• Release Phase: The articulators move to allow air to escape; a loud noise called plosion may occur if air behind the stricture is still under pressure
• Post-Release Phase: What happens immediately after the release.
• Voicing may occur during part or all of the plosive articulation.
• English plosives can be bilabial, alveolar, or velar (see page 29).
• Bilabial plosives: p, b produced by lips being pressed together (Figure 15).
• Alveolar plosives: t, d produced by the tongue blade being pressed against the alveolar ridge (Figure 16).
• Velar plosives: k, g produced by the back of the tongue being pressed against the area where the hard palate ends and the soft palate begins (Figure 17).
• p, t, k (fortis) are always voiceless.
• The voicing of b, d, g (lenis) varies depending on position:
  • Initial Position: at the beginning of a word.
  • Medial Position: between other sounds.
  • Final Position: at the end of a word.
• Initial position plosives (CV): there is very little voicing during the compression phase of b, d, g in slow speech and possibly no voicing at all in rapid speech.
• The plosions of p, t, k are audible, and in the post-release phase, air escapes through the vocal folds, making a sound like 'h', which is called aspiration.
• The plosion of b, d, g is weak and doesn't have aspiration.
• p, t, k is distinguished from b, d, g by aspiration, not voicing.
• b, d, g cannot be preceded by any consonant
• p, t, k can be preceded by s, in this case p, t, k are unaspirated and have a similar sound to b, d, g.
• Medial positions (VCV) may exhibit characteristics of final or initial plosives, depending on the surrounding context relating to the stressed vowels
• Final position plosives (VC): b, d, g have little voicing at the beginning of the compression phase.
• The plosion of both p, t, k and b, d, g is very weak and often inaudible.
• Vowels preceding p, t, k are much shorter than those preceding b, d, g. This effects long or diphthong vowels and is called pre-fortis clipping.

Fricatives

• Fricatives sounds are made air escapes through a narrow passage, producing a hissing sound.
• Fricatives are continuant sounds, capable of being produced without interruption with sufficient lung capacity.
• Fortis fricatives produce louder friction noises than lenis fricatives.
• Lenis fricatives have little or no voicing in initial and final positions, it may be voiced when it occurs between voiced sounds.
• Fortis fricatives shorten preceding vowels in the same way as fortis plosives.
• English fricatives can be labiodental, dental, alveolar, or post-alveolar(see page 40).
• Labiodental fricatives: f, v where the lower lip is raised to come in contact with the upper teeth (Fig. 18).
• Dental fricatives: θ, ð the tongue is placed behind the teeth with the tip touching the inner side of the lower teeth (Fig. 19).
• Alveolar fricatives: s, z the air escapes along the center of the tongue, same place as t, d.
• Post-alveolar fricatives: ∫, ʒ the tongue is in contact with an area slightly further back than s, z.
• f, v, θ, ð, s, z, ∫ are found in initial, medial and final positions.
• Initial and final positions for ʒ are rare.
• Glottal fricatives: h where the narrowing that produces the friction noise is between the vocal folds (glottis).
• h has the quality of the vowel it precedes, h can be considered a voiceless vowel with the quality of the voiced vowel that follows it.
• h usually occurs in initial and medial positions, a slightly fricative sound in this case called breathy voice.
• h can be omitted in normal speech.

Affricates

• Affricates begin as plosives and end as fricatives.
• The plosive is followed immediately by fricative noise.
• Plosive and fricative must be made with the same articulators, they must be homorganic.
• English has tʃ, dʒ.
• Although tʃ, dʒ can be said to be composed of a plosive and a fricative, they are normally regarded as being single, independent phonemes in English.
• The place of articulation of tʃ, dʒ is post-alveolar, same as ʃ, ʒ.
• The t and d components of tʃ, dʒ have a place of articulation slightly further back in the mouth than t and d plosives.
• tʃ is slightly aspirated in the positions where p, t, k are aspirated, tʃ in final position also shortens a preceding vowel.
• tʃ, dʒ often have rounded lips.

Notes on Fortis Consonants

• Vowels, consonants l, m, n, ŋ are shortened when they precede a fortis consonant
• Fortis consonants are articulated with an open glottis.
• With plosives p, t, k, and tʃ (whose beginning component is a plosive), it is possible to produce these sounds with a completely closed glottis, called glottalisation.
• Glottalisation is most widespread with tʃ at the end of a stressed syllable.

Nasals

• In the articulation of vowels and other consonants, the soft palate is raised, preventing air from passing through the nose.
• Nasal consonants involve lowering the soft palate to allow air to escape through the nose while a complete closure is maintained in the mouth.
• All nasals are voiced (lenis).
• There are three types of closure in English nasals:
  • Bilabial: m same as p, b.
  • Alveolar: n same as t, d.
  • Velar: ŋ same as k, g.
• m, n are distributed similarly to plosives, in that they occur in the initial, medial, and final positions.
• Only n is the only English consonant that does not occur initially (with the possible exception of ʒ).
• In a medial position, if ŋ is found in the letters “nk”, a k will always be pronounced.
• In the letters "ng", g is only pronounced if ŋ appears in the middle of a morpheme; it is not pronounced if ŋ occurs at the end of a morpheme.
• This rule isn't applied to comparative and superlative forms of adjectives, i.e. these forms are to be treated as single-morpheme words.
• Only short vowels are regularly found preceding ŋ.

Lateral Approximants

• The articulation of lateral approximant sounds involves a complete closure between the center of the tongue and the roof of the mouth where contact is to be made.
• Air can only escape along the sides of the tongue instead of the center.
• All lateral approximants are voiced (lenis) and continuant.
• l, with an alveolar place of articulation, is the only lateral approximant in English.
• l can occur initially, medially, and finally.
• The realization of l varies depending on different contexts:
  • Before vowels: l resembles an [i] with the front of the tongue raised (a “clear l").
  • Before consonants or a pause: l resembles an [u] with the back of the tongue raised (a "dark l").
  • l can be devoiced and pronounced as a fricative when it follows p, k at the beginning of a stressed syllable.

Approximants

• An approximant is an articulation in which articulators approach each other but not closely enough to produce a complete consonant like a plosive, nasal or fricative.
• Any vowel articulation could be classed as an approximant, but this term is usually for consonants.
• All approximants are voiced (lenis) and continuant.
• Articulation of r involves The tongue tip approaching the alveolar area similarly to t, d without making roof of the mouth contact.
• The tongue is then lightly curled backwards with the tip raised forming a retroflex, moving the tongue tip to a position slightly further back than that for alveolar consonants, also known as post-alveolar.
• Lips are usually slightly rounded.
• r sounds too much like w if lips aren't rounded.
• r sounds in many other languages sometimes involve tongue-palate contact.
• In the BBC accent, r only occurs before vowels.
• Some accents of English do pronounce r in final position and before a consonant.
• Phonetically, j and w sounds are like vowels.
• The articulation of j is practically the front close vowel [i], but very short.
• The articulation of w is similar to [u].
• j and w are used like consonants, and their places of articulation are normally palatal and bilabial respectively.
• In earlier works on phonology, j and w are called semivowels.
• When p, t, k are followed by l, r, j, w, these voiced continuant consonants lose their voicing and become fricative (aspiration).