The main principles of vowel and consonant formation. The articulatory and auditory difference between vowel and consonant phonemes.

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English vowels and consonants in the phonological system

The main principles of vowel and consonant formation. The articulatory and auditory difference between vowel and consonant phonemes.

There are two major classes of sounds traditionally distinguished by phoneticians in any language. They are termed consonants and vowels. The distinction between them is based mainly on auditory effect. Consonants are known to have voice and noise combined, while vowels are sounds consisting of voice only. From the articulatory point of view the difference is due to the work of speech organs. Vowels are formed by means of periodic vibrations of the vocal cords in the larynx. The resulting sound waves are transmitted to resonance chamber - the supra-laryngeal cavities (the pharynx and the mouth cavity), where vowels receive their characteristic tamber. The quality of vowels depends on the shape and size of the resonance chamber which is made to vary, depending on the different positions of the tongue in the mouth cavity, on any slight alternations in the position of the back walls of the pharynx, in the position of the soft palate and of the lips, which form the outlet of the resonance chamber. In vowel articulation no obstruction is made and the muscular tension is spread all over the speech organs. The force of exhalation is rather weak for it is expended when the air stream passes through the larynx and causes the vocal cords to vibrate. In case of consonants various obstructions are made in one of the supra-laryngeal cavities. So consonants are characterized by so-called close articulation, that is by a complete, partial or intermittent blockage of the air-passage by an organ or organs. The closure is made in such a way that the air-stream is blocked or hindered or otherwise gives rise to audible friction which acoustically results in noise. In consonant articulation the muscular tension is concentrated at the point of obstruction and a stronger air stream is required. According to the degree of noise consonants are divided into noise and sonorant. Sonorants are sounds intermediate between consonants and vowels because they have features common to both, that is why some sonorants are called semivowels. In the production of sonorants the obstruction is complete or incomplete but not narrow enough to produce noise. In other words, the air passage between the two organs of speech is much wider than in the production of noise consonants. In sonorants articulation muscular tension is concentrated in the place of obstruction, but the exhaling force is rather weak.

Summing up the articulatory difference between vowels, noise consonants and sonorants, one can single out three criteria:

- the presence or absence of obstruction to the air-stream;

- the concentrated or diffused character of muscular tension;

- the force of exhalation.

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