Routledge dictionary of language and linguistics - Developers

Reference
Rosner, B.S. and J.B. Pickering. The perception of vowels. Oxford.
vowel block
Schematic representation of the vowels according to the three dimensions (a) high
(closed) vs low (open), (b) front vs back, (c) rounded (non-spread) vs unrounded
(spread). In the graphic representation of the IPA chart, these three dimensions are shrunk
to a pseudo-two-dimensional trapezium ( vowel chart).
phonetics
Dictionary of language and linguistics 1276
References
vowel chart
Schematized representation of the vowels in a geometric form. The classification rests on
the physiological and articulatory actions of the tongue and lips in the production of the
vowels. From the vowel chart originally developed by C.F.Hellwag (1754–1835), in
which [i], [u], and [a] formed the corners of the geometric figure, the vowel ‘square’ (or
trapezoid) was developed as the a-sound was differentiated into a front æ and a back a.
The vowel chart has a three-dimensional basis: (a) vertical tongue or jaw height (high,
middle, deep); (b) horizontal tongue placement (front, neutral/central, back); and (c)
shape of lips (rounded, unrounded) ( vowel block). The vowel chart is recommended
by the International Phonetic Association (IPA) for use as a classificatory schema for all
vowel systems. ( also phonetic transcription)
References
Hellwag, C.F. 1781. Dissertatio de formatione loquelae. Tübingen. (Repr. Heilbronn, 1886.)
Jones, D. 1950. The phoneme, its nature and use. Cambridge.
phonetics