In many languages, bilabials such as "m," "p," and "b," as well as the low vowel "a," are among the easiest to produce.
One hypothesis is that the original vowel system was essentially like that of Finnish, which has eight vowel sounds: i, ü, u, e, ö, o, ä, a (ü spelled y in the standard orthography and ö are front rounded vowels, as in German; ä is a low front vowel, as a in cat).
If, for example, the transcription were to be used in teaching pronunciation, the difference between the aspirated and unaspirated allophones of /P/ might be represented by transcribing pan as [phan] and span as [span]; or the vowel phoneme in each of these words might be designated by the more specific symbol, which represents a low front vowel of a certain type.
(See, for example, August 2008 on a low central vowel and August 2011 on central approximants).
In CGVG and CGVN, the main vowel is 100% [a], the only low vowel in Mandarin, whereas in other syllable forms, the main vowel is mostly not [a]; this could explain why CGVG and CGVN have the longest mean duration.
The results are as follows: (1) the highest nasalance score among the Vietnamese normal vowels is the low vowel /a/; however, that of Korean normal vowels is the high vowel /i/.
Soprano singing /A,o,u, ε/ vowels with a low vocal effort tend to adjust their first formant with the first harmonic f 010010
In this case, there is some evidence of vocal tract resonances tuning as a function of f 0. Soprano singing /A,o,u, ε/ vowels with a low vocal effort tend to adjust their second formant to the second harmonic 2f 0 [10].
Somewhat fewer than half of the languages have developed tonal contrasts from original syllable final glottalization; e.g., Proto-Athabaskan *teɬšɬ 'mat' > Tsek'ene tèl, where indicates an unattested form, ɬ represents glottalization, and is a low-tone vowel.
Across these languages, they found a remarkable similarity among the "Huhs?" All the words had a single syllable, and they were typically limited to a low-front vowel, something akin to an "ah" or an "eh".
