Koa Phonology I: Vocalism

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Despite the fact that phonetics and phonology are arguably my favorite areas of linguistics (with honorable mention to historical change), I've managed to go 18 years on this blog saying very little about these things. It's time to make amends! This will be the first in a series in which I'll try to describe Koa's phonology with the rigor it deserves.

1. Koa Phonology

Having been conceived as an international auxiliary language, it may be helpful as a conceptual device to imagine a world in which Koa is spoken as an L2 by people from many different language backgrounds. In such a world, we would inevitably see a great deal of regional variation in the actual realization of Koa's phonology; it was in fact an original design parameter that the phonology expect and allow for this variation. Though we attempt here a description of a neutral standard, then -- coincidentally the dialect of the author -- it is important to bear in mind that no single region is intended as the language's center of gravity, validity or prestige. From a prescriptive perspective, L1 constraints may drive the precise realization of these phonemes freely as long as they remain consistent and distinct from one another.

For this reason, each section below describes both the standard and the range of expected acceptable variation we might expect to encounter around the world.

1.1 Vocalism
1.1.1 Monophthongs

Koa has the five short vowels typical of many world languages, and three long vowel phonemes; vowels are rounded only if [+back]:

	Short				Long
	Front	Central	Back		Front	Central	Back
High	i [ɪ]		u [ʊ]		i: [iː]		u: [uː]
Mid	e [ɛ]		o [ɔ]
Low		a [ɑ]				a: [ɑː]

Long vowels are held for approximately 1.5 times the duration of short vowels. Note that mid vowels lack a long counterpart, long */e:/ and */o:/ having merged with /ei̯/ and /ou̯/ respectively (see 1.1.2 Diphthongs). Short /a/ tends to be rather more front than long /a:/. Vowel quality and quantity do not vary with stress or position.

Note: /i/ and /u/ are very peripheral and notably closer than the usual realization of the corresponding phonemes in e.g. English or German.

1.1.1.1 Variation

Provided that all phonemes remain distinct from each other, we may see variation in the following areas:

* Long vowels held for the duration of two full short vowels e.g. /a:/ → [ɑːː], or pronounced as two distinct short vowels in sequence e.g. [ɑɑ]
* Tensing of high vowels to [i u] or further laxing to [ɪ̞ ʊ̞]
* Closer mid vowels [e o]
* Frontness of /a/ anywhere from [a] to [ɑ], some rounding towards [ɒ], or some raising towards [ɐ] or [æ]
* Unrounding of back vowels, particularly /u/ as [ɯ] or [ɨ]
* Fronting of /u/ to [ʏ] or [ʉ]

* Full centralization of at most one phoneme, e.g. /a/ as [ə] or [ʌ]

Whatever the exact realization of each phoneme, it is strongly preferred that it remain consistent in quality in all positions to ease parsing by speakers of other dialects.

1.1.1.2 Devoicing

There is a tendency in rapid speech for unstressed non-initial high short vowels partially or completely to lose their voicing -- though not their duration -- following a voiceless consonant: /ákuci/ → [ˈɑkʊ̥ʃi] "hunter," /ti‿élate/ → [tɪ̥ˈɛlɑtɛ] "this life," /àpu‿taéma/ → [ˌɑpʊ̥tɑˈɛmɑ] "help his parents." This may occur even if the high vowel is stressed within its own word, but not its larger prosodic group: /ka‿somaéte‿mokùne/ → [mɔˌku̥nɛ] "what you're doing together." Utterance-final devoicing is possible but less common.

1.1.2 Diphthongs

Combinations of any two unlike vowels are possible within a single lengthened syllable. Such diphthongs exist in two types: falling (short) and balanced (long).

Falling: Where the origin is non-high and the target is high, the sequence is realized as a falling diphthong at approximately 1.2 times the duration of a short monophthongal vowel: ai [ɑɪ̯], ei [eɪ̯], oi [ɔɪ̯], au [ɑʊ̯], eu [ɛʊ̯], ou [oʊ̯].

Balanced: In other cases, diphthongs can be considered balanced in that neither the origin nor target is fully non-syllabic; the origin tends to have slightly greater duration than the target. These diphthongs are approximately the length of a long vowel, that is 1.5 times that of a short vowel: ae [ɑ͡ɛ], ao [ɑ͡ɔ], ea [ɛ͡ɑ], eo [ɛ͡ɔ], ia [ɪ͡ɑ], ie [ɪ͡ɛ], io [ɪ͡ɔ], iu [ɪ͡ʊ], oa [ɔ͡ɑ], oe [ɔ͡ɛ], ua [ʊ͡ɑ], ue [ʊ͡ɛ], ui [ʊ͡ɪ], uo [ʊ͡ɔ].

1.1.2.1 Variation

Alternative possible realizations include:

- Pronunciation of diphthongs as two consecutive full short vowels
- Diphthongs with an initial high vowel as rising: ia [ɪ̯ɑ], ie [ɪ̯ɛ], ua [ʊ̯ɑ], ue [ʊ̯ɛ], etc.
- Centralization of the origin of /ai/ and /au/ → [əɪ̯ əʊ̯], [ʌɪ̯ ʌʊ̯], [ɐɪ̯ ɐʊ̯], etc.

1.1.3 Orthography

Koa vowels are written identically to the phonemic symbols here used, whether single or in combination, except that long vowels are shown orthographically by doubling: aa /a:/ etc.