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Phonemes


Evan Kirshenbaum created an ASCII transcription of the International Phonetic Alphabet (IPA)[1], [2]. As well as using ASCII characters for specific IPA phonemes, this transcription provides a set of 3-letter feature abbreviations allowing a phoneme to be described as a sequence of features.

This document extends Evan Kirshenbaum’s feature set to be able to describe the different phonemes in the IPA and as are used in the various languages of the world.

The goal of this document is not to provide a detailed guide on phonetics. Nor is it intended to be able to accurately record differences in IPA diacritics. Instead, it is designed to be a transcription guide for authors of espeak-ng languages and voices on how to specify phonemes so that the IPA and feature transcriptions are consistent.

Phoneme Transcriptions

The following table lists phonetic transcription schemes based on the International Phonetic Alphabet (IPA):

BCP47 Variant Name Transcription Name Encoding
foncxs Conlang X-SAMPA (CXS) ASCII
fonipa International Phonetic Alphabet (IPA) Unicode
fonkirsh Kirshenbaum (ASCII-IPA) ASCII
fonxsampa X-SAMPA ASCII

NOTE: The foncxs and fonkirsh variant names are not defined in the IANA language subtag registry. Instead, they are private use extensions defined in the bcp47-data project.

Consonants

Manner of Articulation

Feature Name
nas nasal
stp plosive (stop)
afr affricate
frc fricative
flp tap/flap
trl trill
apr approximant
clk click
ejc ejective
imp implosive
vwl vowel

The vwl phonemes are described using vowel height and backness features, while consonants (the other manners of articulation) are described using place of articulation features.

Additionally, the manner of articulation can be refined using the following features:

Feature Name
lat lateral
sib sibilant

Place of Articulation

Feature Name
blb bilabial
lbd labiodental
bld bilabial-labiodental
dnt dental
alv alveolar
pla palato-alveolar
rfx retroflex
alp alveolo-palatal
pal palatal
vel velar
lbv labio-velar
uvl uvular
phr pharyngeal
glt glottal

The bld place of articulation is used for afr consonants that have a blb onset and a lbd release, e.g. in the German [p͡f] consonant.

NOTE: The IPA charts make a distinction between pharyngeal and epiglottal consonants, but Wikipedia does not. This model uses the Wikipedia descriptions.

Voice

Feature Name
vls voiceless
vcd voiced

Gemination

Gemination is found in several languages including Italian and Japanese. It is also present in the suprasegmental phonology between words such as “lamppost” and “evenness”.

Some linguists use the long suprasegmental for geminate consonants. The eSpeak NG convention is to use consonant length for phonation when consonant length is distinct without gemination occurring.

The way gemination is represented in eSpeak NG is to duplicate the phonemes, with the first phoneme using the unx feature. For example, [n̚.n] for a geminated [n]. This describes how with the stp and nas consonants, the mouth remains closed (unx) for the first of the geminated consonants.

Vowels

Height

Feature Name
hgh close (high)
smh near-close (semi-high)
umd close-mid (upper-mid)
mid mid
lmd open-mid (lower-mid)
sml near-open (semi-low)
low open (low)

Backness

Feature Name
fnt front
cnt center
bck back

NOTE: The smh vowels ([ɪ], [ʏ], [ʊ]) are more cnt than the other vowels. However, this distinction is not needed to classify these vowels, so is not included in the phoneme model described in this document.

Rounding

Feature Name
unr unrounded
rnd rounded

Diacritics

Articulation

Feature Name
lgl linguolabial
idt interdental
dental
apc apical
lmn laminal
advanced
retracted
centralized
mid-centralized
raised
lowered

The articulations that do not have a corresponding feature name are recorded using the features of their new location in the consonant or vowel charts, not using the features of the base phoneme.

Air Flow

Feature Name
egs egressive
igs ingressive

Phonation

Feature Name
brv breathy voice
slv slack voice
stv stiff voice
crv creaky voice
glc glottal closure

Rounding and Labialization

Feature Name
ptr protruded
cmp compressed

The degree of rounding/labialization can be specified using the following features:

Feature Name
mrd more rounded
lrd less rounded

Syllabicity

Feature Name
syl syllabic
nsy non-syllabic

Consonant Release

Feature Name
asp aspirated
nrs nasal release
lrs lateral release
unx no audible release (unexploded)

Co-articulation

Feature Name
pzd palatalized
vzd velarized
fzd pharyngealized
nzd nasalized
rzd rhoticized

Tongue Root

The tongue root position can be specified using the following features:

Feature Name
atr advanced tongue root
rtr retracted tongue root

Fortis and Lenis

Feature Name
fts fortis
lns lenis

The extended IPA[7] ◌͈ and ◌͉ diacritics are used to specify lesser (lns) and greater (fts) oral pressure than the unmodified voiced or voiceless phoneme. This distinction is made by the Ewe, Tabasaran, Archi, and other languages[8].

Where fortis and lenis are used to contrast consonant durations (e.g. in the Jawoyn, Ojibwe, and Zurich German languages[8]), the length suprasegmentals are used instead.

Suprasegmentals

Length

Feature Name
est extra short
hlg half-long
lng long
elg extra long

References

  1. Kirshenbaum, Evan, Representing IPA phonetics in ASCII (HTML). 1993.

  2. Kirshenbaum, Evan, Representing IPA phonetics in ASCII (PDF). 2001.

  3. International Phonetic Association, The International Phonetic Alphabet and the IPA Chart. 2015. Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).

  4. Wikipedia. International Phonetic Alphabet. 2017. Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).

  5. Dunn, R. H., Cainteoir Text-to-Speech Phoneme Features. 2013-2015.

  6. Wikipedia. Voiced glottal fricative. 2017, Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).

  7. Wikipedia. Extensions to the International Phonetic Alphabet. 2017, Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).

  8. Wikipedia. Fortis and lenis. 2017, Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).

  9. Wikipedia. Place of articulation. 2017, Creative Commons Attribution-Sharealike 3.0 Unported License (CC-BY-SA).