English Phonetics: Consonants and Allophonic Variations
Consonant Production
Homorganic Nasal Assimilation
In English, if a nasal and an oral stop belong to the same syllable or if the nasal is in a stressed syllable, the oral stop influences the preceding nasal consonant. The nasal assimilates to the place of articulation of the following consonant, resulting in both sounds sharing the same place of articulation.
Close Vowels
Close vowels have a limited degree of mouth opening, such as the high vowel /i/.
/b/ Production
Air expelled from the lungs vibrates the vocal cords. The velum is raised, directing air into the mouth where it is momentarily blocked by the lips. Upon lip opening, a slight explosion is heard. /b/ is a voiced bilabial plosive.
/k/ Production
The vocal cords are held apart, preventing vibration. The raised velum directs air into the mouth where it is momentarily blocked by the back of the tongue touching the velum. Upon release, a slight explosion is heard. /k/ is a voiceless velar plosive.
/n/ Production
Air expelled from the lungs vibrates the vocal cords. The lowered velum directs air into the nasal cavity. In the mouth, the tongue contacts the alveolar ridge. /n/ is a voiced alveolar nasal.
/l/ Production
Air expelled from the lungs vibrates the vocal cords. The raised velum directs air into the mouth. The tongue tip touches the alveolar ridge, but raised sides allow air to escape laterally. /l/ is a voiced alveolar lateral approximant.
/t/ Production
Air passes freely through the glottis without vocal cord vibration. The raised velum directs air into the mouth, where it is blocked by the tongue tip against the alveolar ridge. Upon release, a slight explosion is heard. /t/ is a voiceless alveolar plosive.
/v/ Production
Air expelled from the lungs vibrates the vocal cords. The raised velum directs air into the mouth. A partial obstruction formed by the lower lip and upper teeth creates audible friction as air passes through. /v/ is a voiced labio-dental fricative.
/dʒ/ Production
Air expelled from the lungs vibrates the vocal cords. The raised velum directs air into the mouth, where an occlusion is made in the post-alveolar region. The slow release of the articulators creates friction. /dʒ/ is a voiced post-alveolar affricate.
/h/ Production
Air expelled from the lungs creates turbulence in the glottis without vocal cord vibration. /h/ is a voiceless glottal fricative.
English Allophonic Variants
Aspiration
/p/, /t/, and /k/ are aspirated before vowels at the beginning of a stressed syllable and word-initially in unstressed syllables. Aspiration is a delay in the onset of vocal fold vibration. Voice Onset Time (VOT) measures the time between the release of the plosive and the start of vocal fold vibration.
Consonants can be described as lenis (voiced, weak breath force) or fortis (voiceless, strong breath force). Vowels are shortened before fortis consonants (e.g., “neat” vs. “need”). This is known as pre-fortis clipping.
Devoicing
Devoicing occurs: (a) with approximants (/l/, /r/, /j/, /w/) following voiceless obstruents (plosives, fricatives, affricates); and (b) with voiced obstruents in final position.
Velarization of /l/
Dark, velarized /l/ occurs in syllable codas (e.g., “tail”) with a raised tongue body. Clear /l/ occurs in onsets (e.g., “lake”) with a neutral tongue body. Vocalized /l/ results from loss of tip contact in dark /l/ articulation (e.g., “child”).
Tapping of Alveolar Stops
Glottalization
The glottal stop avoids hiatus, occurs before word-initial stressed vowels, and as an allophone of /t/ between vowels, at the end of a syllable, and before syllabic /n/ and /l/.
Linking and Intrusive /r/
Linking /r/ is an etymological word-final /r/ used to prevent hiatus. Intrusive /r/ is an unetymological /r/ inserted word-finally to avoid hiatus (e.g., “I saw her”).