ARPABET (also spelled ARPAbet) is a set of phonetic transcription codes developed by Advanced Research Projects Agency (ARPA) as a part of their Speech Understanding Research project in the 1970s. It represents phonemes and allophones of General American English with distinct sequences of ASCII characters. Two systems, one representing each segment with one character (alternating upper- and lower-case letters) and the other with one or two (case-insensitive), were devised, the latter being far more widely adopted.

ARPABET has been used in several speech synthesizers, including Computalker for the S-100 system, SAM (Software Automatic Mouth) for the Atari 8-bit computers and Commodore 64, the Say utility shipped with the Amiga, TextAssist for the PC and Speakeasy from Intelligent Artefacts which used the Votrax SC-01 speech synthesiser IC. It is also used in the CMU Pronouncing Dictionary. A revised version of ARPABET is used in the TIMIT corpus.

Symbols

Stress is indicated by a digit immediately following a vowel. Auxiliary symbols are identical in 1- and 2-letter codes. In 2-letter notation, segments are separated by a space.

Vowels
ARPABETIPAExample(s)
1-letter2-letter
aAAɑ~ɒbalm, bot (with father–bother merger)
@AEæbat
AAHʌbuck
cAOɔcaught, story
WAWbout
xAXəcomma
—N/aAXRɚletter, forward
YAYbite
EEHɛbet
RERɝbird, foreword
eEYbait
IIHɪbit
XIXɨroses, rabbit
iIYibeat
oOWboat
OOYɔɪboy
UUHʊbook
uUWuboot
—N/aUXʉdude
Consonants
ARPABETIPAExample
1-letter2-letter
bBbbuy
CCHChina
dDddie
DDHðthy
FDXɾbutter
LELbottle
MEMrhythm
NENbutton
fFffight
gGɡguy
hHH or Hhhigh
JJHjive
kKkkite
lLllie
mMmmy
nNnnigh
GNX or NGŋsing
—N/aNXɾ̃winter
pPppie
QQʔuh-oh
rRɹrye
sSssigh
SSHʃshy
tTttie
TTHθthigh
vVvvie
wWwwise
HWHʍwhy (without wine–whine merger)
yYjyacht
zZzzoo
ZZHʒpleasure
Stress and auxiliary symbols
ABDescription
0No stress
1Primary stress
2Secondary stress
3...Tertiary and further stress
-Silence
!Non-speech segment
+Morpheme boundary
/Word boundary
#Utterance boundary
:Tone group boundary
:1 or .Falling or declining juncture
:2 or?Rising or internal juncture
:3 or .Fall-rise or non-terminal juncture

TIMIT

In TIMIT, the following symbols are used in addition to the ones listed above:

SymbolIPAExampleDescription
AX-Hə̥suspectDevoiced /ə/
BCLobtain[b] closure
DCLwidth[d] closure
ENGŋ̍WashingtonSyllabic [ŋ]
GCLɡ̚dogtooth[ɡ] closure
HVɦaheadVoiced /h/
KCLdoctor[k] closure
PCLaccept[p] closure
TCLcatnip[t] closure
PAU—N/a—N/aPause
EPI—N/a—N/aEpenthetic silence
H#—N/a—N/aBegin/end marker

See also

External links