The International Phonetic Alphabet (IPA) consists of more than 100 letters and diacritics. Before Unicode became widely available, several ASCII-based encoding systems of the IPA were proposed. The alphabet went through a large revision at the Kiel Convention of 1989, and the vowel symbols again in 1993.[1] Systems devised before these revisions inevitably lack support for the additions they introduced.
Only language-neutral systems are discussed below because language-dependent ones (such as ARPABET) do not allow for a systematic comparison.
Presented here is the scheme used for representing phonemes in the database of phonological inventories. Consequently, it is not designed for transcription of multiple segments and does not have symbols for values not found phonemically in the languages sampled.
Only the symbols in the latest IPA chart are included. The numbers in the leftmost column, according to which the symbols are sorted, are the IPA Numbers. Some of the IPA symbols to which a system lacks a corresponding symbol may still be represented in that system by use of a modifier (diacritic), but such combinations are not included unless the documentation explicitly assigns one for the value.
^ abcL represents either a voiceless alveolar lateral fricative, a velar approximant, or a velarized alveolar lateral approximant in the Usenet IPA/ASCII transcription.
^ abc! represents either an alveolar or palatal click in the Usenet IPA/ASCII transcription.
^ ab- represents either retracted or "velarized or pharyngealized" in Millar & Oasa's system.
^ ab¿ and ¡ are not part of ASCII, but are nonetheless proposed as encoding advanced and retracted tongue root, respectively, in Worldbet.
^. represents either raised or palatalized in Millar & Oasa's system.
^ ab* represents either non-syllabic or extra-short in Millar & Oasa's system.
^)) representing a tie bar is placed after both segments, as in ts)), in Branner's system.
References
^International Phonetic Association (1993). "Council actions on revisions of the IPA". Journal of the International Phonetic Association. 23 (1): 32–34. doi:10.1017/S002510030000476X. S2CID249420050.
^Millar, J. B.; Oasa, H. (1981). "Proposal for ASCII coded phonetic script". Journal of the International Phonetic Association. 11 (2): 62–74. doi:10.1017/S0025100300002279. S2CID146352996.
^Gómez-Vilda, Pedro; Ferrández-Vicente, José Manuel; Rodellar-Biarge, Victoria; Álvarez-Marquina, Agustín; Mazaira-Fernández, Luis Miguel; Martínez-Olalla, Rafael; Muñoz-Mulas, Cristina (2009). "Detection of Speech Dynamics by Neuromorphic Units". In Mira, José; Ferrández, José Manuel; Álvarez, José R.; de la Paz, Félix; Toledo, F. Javier (eds.). Methods and Models in Artificial and Natural Computation: A Homage to Professor Mira's Scientific Legacy – Third International Work-Conference on the Interplay Between Natural and Artificial Computation, IWINAC 2009, Santiago de Compostela, Spain, June 22-26, 2009, Proceedings, Part I. Springer. pp. 67–78. doi:10.1007/978-3-642-02264-7_8. ISBN978-3-642-02263-0. Page 74.
^Hieronymus, James L. (1994). "ASCII Phonetic Symbols for the World's Languages: Worldbet". AT&T Bell Laboratories Technical Memorandum. CiteSeerX10.1.1.225.9914.