Extensions to the International Phonetic Alphabet

The extensions to the International Phonetic Alphabet, also extIPA symbols for disordered speech or simply the extIPA (Ext-IPA), are a set of letters and diacritics designed to augment the International Phonetic Alphabet for the phonetic transcription of disordered speech. Some of the symbols are occasionally used for transcribing features of normal speech.

Many sounds found only in disordered speech are indicated with diacritics, though an increasing number of dedicated letters are used as well. Special letters are included to transcribe the speech of people with lisps and cleft palates. The extIPA repeats several standard-IPA diacritics that are unfamiliar to most people but transcribe features that are common in disordered speech. These include preaspiration ⟨ʰ◌⟩, linguolabial ⟨◌̼⟩, laminal fricatives [s̻, z̻] and ⟨*⟩ for a sound (segment or feature) with no available symbol (letter or diacritic). The novel transcription ⟨ɹ̈⟩ is used for an English molar-r, as opposed to ⟨ɹ̺⟩ for an apical r; these articulations are indistinguishable in sound and so are rarely identified in non-disordered speech.

Sounds not found in non-disordered speech include fricative nasals (a.k.a. nareal fricatives) and percussive consonants. Sounds sometimes found in the world's languages that do not have symbols in the IPA include denasals and fricatives that are simultaneously lateral and sibilant.

Letters

The full letters added by the extIPA are the following:

velopharyngeal	ʩ ʩ̬	Velopharyngeal fricative (snoring sound; often occurs with a cleft palate)
Lateral	ʪ	Voiceless grooved lateral alveolar fricative, [ɬ͡s] (a laterally lisped /s/, with simultaneous airflow through the sibilant groove in the tongue and across the side of the tongue) intended for a lateral lisp
	ʫ	Voiced grooved lateral alveolar fricative, [ɮ͡z] (a laterally lisped /z/)
Percussive	ʬ	Bilabial percussive (smacking lips)
	ʭ	Bidental percussive (gnashing teeth)
	¡	Sublaminal lower-alveolar percussive (tongue slap)

The symbol ⟨¡⟩ is used with the alveolar click for [ǃ¡], an alveolar click with percussive release, a "cluck".

Diacritics

The ExtIPA has widened the use of some of the regular IPA symbols, such as ʰp for pre-aspiration, tʶ for uvularization, or s̼ for a linguolabial sibilant, as well as adding some new ones. Some of the ExtIPA diacritics are occasionally used for non-disordered speech, for example for the unusual airstream mechanisms of Damin.

One modification is the use of subscript parentheses around the phonation diacritics to indicate partial phonation; a single parenthesis at the left or right of the voicing indicates that it is partially phonated at the beginning or end of the segment. These conventions may be convenient for representing various voice onset times. Phonation diacritics may also be prefixed or suffixed rather than placed directly under the segment to represent relative timing.

Partial (de)voicing
₍s̬₎	partial/central voicing of [s]	₍z̥₎	partial/central devoicing of [z]
₍s̬	initial voicing	₍z̥	initial devoicing
s̬₎	final voicing	z̥₎	final devoicing
Timing
̬z	pre-voiced [z]	z ̬	post-voiced [z]
a ̰	[a] with a creaky offglide

The transcriptions for partial voicing and devoicing may be used in either the sense of degrees of voicing or in the sense that the voicing is discontinuous. For the former, both parentheses indicate the sound is mildly (partially) voiced throughout, and single parentheses mean a partial degree of voicing at the beginning or end of the sound. For the latter, both parentheses mean the sound is (de)voiced in the middle, while the single parentheses mean complete (de)voicing at the beginning or end of the sound.

Altering the position of a diacritic relative to the letter indicates that the phonation begins before the consonant or vowel does or continues beyond it. The voiceless ring and other phonation diacritics can be used in the same way if needed. For example, ⟨p˳a⟩ indicates that voicelessness continues past the [p], equivalent to ⟨pʰa⟩.

Other ExtIPA diacritics are:

Airstream mechanism
p↓	Ingressive airflow	ǃ↑	Egressive airflow
Phonation
p˭	Unaspirated	ʰp	Pre-aspiration
Nasalization
n͋    v͋	Nareal fricative or nasal fricative escape (audible turbulent airflow through the nostrils, as with a nasal lisp)	s͌	Velopharyngeal friction (turbulent airflow through the velopharyngeal port at the back of the nose)
m͊	Denasal (as with a headcold; complements the nasal diacritic)
Articulatory strength
f͈	Strong articulation (not necessarily fortis)	v͉	Weak articulation (not necessarily lenis)
Articulation
v͆	Dentolabial	n̪͆    h̪͆	Interdental (on a coronal letter) or bidental (on a glottal letter)
s͇    f͇	Alveolar (on a coronal letter) or labioalveolar (on a labial letter, as with a severe overbite)	s͎	Whistled
s͍	Labial spreading (complements the diacritics for rounding – see rounded vowel)	s̻ z̻	laminal fricatives (including lowered tongue tip)
ɹ̈	bunched-r (molar-r)	ɹ̺	apical-r
s͕    s͔	Offset to the left and right, respectively
Timing
s͢θ	Slurred/sliding articulation (a consonantal diphthong, moving from one articulation to another within the time of a single segment)	p\p\p	Stutter (reiterated articulation)

The VoQS voice-quality symbols take IPA and extended-IPA diacritics, and also several additional diacritics that are potentially available for the extIPA. At least the subscript dot for 'whisper' is sometimes found in IPA transcription.

Prosodic notation

The Extended IPA has adopted bracket notation from conventions transcribing discourse. Parentheses are used to indicate mouthing (silent articulation), as in (ʃːː), a silent sign to hush. Parentheses are also used to indicate silent pauses, for example (...). Double parentheses indicate extraneous, obscured or unintelligible sound, as in ((2 syll.)), two audible but unidentifiable syllables. [These have dedicated characters in Unicode: ⸨2 syll.⸩.] A empty circle is used for an indeterminate segment; Ⓒ is identified only as a consonant, Ⓕ as a fricative, ⓟ as probably a [p], etc. Curly brackets with Italian musical terms are used for phonation and prosodic notation, such as [{_falsetto hɛlp _falsetto}] and terms for the tempo and dynamics of connected speech. These are subscripted within a {curly brace} notation to indicate that they are comments on the intervening text.

(.)	Short pause	(..)	Medium pause	(...)	Long pause	(1.2)	1.2-second pause
f	Loud speech ('forte')	[{f lɑʊd f}]		ff	Louder speech ('fortissimo')	[{ff lɑʊdɚ ff}]
p	Quiet speech ('piano')	[{p kwaɪət p}]		pp	Quieter speech ('pianissimo')	[{pp kwaɪətɚ pp}]
allegro	Fast speech	[{allegro fɑːst allegro}]		lento	Slow speech	[{lento sloʊ lento}]
crescendo, rallentando, and other musical terms may also be used.

The VoQS conventions use similar notation for voice quality.

Chart

Integrating the extIPA with the standard IPA, the following distinctions of place are made (illustrated with fricatives):

Places of articulation in extIPA and standard IPA

bi- labial	labio- dental	labio- alveolar	dento- labial	bi- dental	linguo- labial	inter- dental	alve- olar	post- alveolar	retro- flex	alveolo- palatal	pal- atal	velar	uvu- lar	velo- phary- ngeal	upper phary- ngeal	glot- tal
ɸ β	f v	f͇ v͇	f͆ v͆	h̪͆ ɦ̪͆	θ̼ ð̼	θ̪͆ ð̪͆	s z	ʃ ʒ	ʂ ʐ	ɕ ʑ	ç ʝ	x ɣ	χ ʁ	ʩ ʩ̬	ħ ʕ	h ɦ

References

• Martin Ball, John Esling & B Craig Dickson (1995) "The VoQS system for the transcription of voice quality", Journal of the International Phonetic Association 25 (2): 71–80.
• M Duckworth, G Allen, W Hardcastle & M Ball (1990) "Extensions to the International Phonetic Alphabet for the transcription of atypical speech", Clinical Linguistics and Phonetics 4: 273–280.
• Barry Hesselwood & Sara Howard (2008) "Clinical Phonetic Transcription". In Ball et al. (eds.) The Handbook of Clinical Linguistics. Blackwell.
• Martin Ball & Orla Lowry (2001, 2008) Methods in Clinical Phonetics, "Transcribing Disordered Speech".

External links

• Chart of extended IPA symbols for disordered speech (PDF, revised to 2008)
• Pronunciation videos of consonants in the main extIPA chart as of 2008