Summary. Phoneticsis a science of speech sounds used in communication

Phonetics is a science of speech sounds used in communication. It aims to provide a set of features to describe how speech sounds are made by speakers (production), how speech sounds are perceived by listeners (perception) and how speech sounds can be processed (analysis and synthesis). Thus phonetics may be articulatory, auditory (perceptual) and acoustic.

Communication depends on mutual intelligibility and cultural aware­ness. All the phonetic aspects, such as pronunciation of segments (consonants and vowels) and suprasegmental features (word stress, rhythm and intonation) are relevant for successful communication.

All English and Russian sounds have the same air stream mechanism: they are produced as we breathe out (pulmonic, egressive). The main pro­cesses in production are: initiation process (in the lungs), phonation pro­cess (in the larynx), articulation process (in the oral cavity), oro-nasal process (the velum and the nasal cavity).

International Phonetic Alphabet (IPA) is a system of symbols also called transcription in which one sound corresponds to one symbol. It has been devised by a body of linguists, International Phonetic Association (also abbreviated as IPA) for phoneticians to represent the sounds of all human languages. It is used in dictionaries and manuals to represent the pronunciation of words.

Speech sounds fall into classes according to their phonetic properties. All speech sounds are either consonants or vowels. Consonants have some obstruction of the air stream in the vocal tract, and the location of the obstruction defines their place of articulation (bilabial, labiodental, dental, alveolar, palatal, velar, uvular, glottal). We can also define them according to the articulators (coronal, apical, lamina!, dorsal) which are just as rele­vant as the points of articulation for comparing groups of English and Rus­sian coronal consonants (apical vs. Iaminal, alveolar vs. dental).

There maybe more than one place of obstruction. Secondary articulations are: labialization, velarization, palatalization, pre-glottalization. Palatalization vs. velarization contrast is distinctive in the system of Russian consonants ("soft" vs. "hard").

Consonants are further classified according to their manner of articulation: they may be voiced or voiceless, oral or nasal. They may be stops, fricatives, affricates, approximants (liquids and glides). Voiceless sounds may be aspirated or unaspirated. Approximants may be trills or flaps; they may be central or lateral. "Voiceless consonants are believed to be pronounced with greater force (fortis) in comparison with voiced consonants which are weaker (lenis).

English voiced consonants lose voice distinction in the word-initial position and, partially, in the word-final position. Russian voiced consonants become fully devoiced in the word-final position. English loss of voice distinction is compensated by aspiration of truly voiceless (fortis) consonants in the word-initial position before a stressed vowel. In the word-final posi­tion the loss of voice is compensated by the length of the preceding vowel.

The properties of sounds are modified by their phonetic environment.

Vowels form the nucleus of the syllable. They differ according to the position of the tongue and lips. According to the height of the tongue: high, mid-high, mid-low, low; front-back position: front, central, back; lip position: rounded and unrounded. The vowel space of English has the form of a trapezium; the Russian vowel space, as in many other world languages, is shaped like a triangle (bottomed up).

The vowels of English may be tense or lax. Tense vowels are longer in duration than lax vowels (by 1.5 in British English and by 1.2 in American English), and they normally appear in open syllables. Such properties of vowels as checked or free, stressed or unstressed are also manifested only in a syllable.

The tradititional division of English vowels is into (historically) long, (historically) short vowels and diphthongs. In English, long vowels and diphthongs are more peripheral sounds which need more time and effort for their articulation, and they also have specific vowel quality to identify them. Today the terms tense and lax are used as cover terms for the two groups of vowels, while each particular vowel is identified by its quality which depends on the height and the front-back position of the tongue.

'Vowels, like consonants, maybe nasal and oral, though most vowels in all languages are oral. In English vowels are nasalized before a nasal consonant, which is more noticeable in American English. There are other vowel features which are affected by coarticulation with consonants. Length depends on the presence of fortis-lenis consonants to follow the vowel. It is graded: vowels are the longest in an open syllable, shorter before a lenis consonant and the shortest before a fortis consonant. The length of the vowel increases in a stressed syllable, it decreases in a polysyllabic word. Thus English vowels are mostly affected by consonants which follow them (VC connection, typical for closed syllables) in length, nasalization and velarization. In Russian there is a close link between the vowel and the consonant which precedes it (CV connection, typical for open syllables), with palatalization-velarization feature spreading over the CV complex ("soft" consonant + front vowel, for instance).

Phonetics is concerned with human speech in many ways. Language acquisition is an area which demonstrates how speech sounds are first discriminated and then pronounced in early childhood.

Intonation is the first kind of linguistic structuring in the vocalization of the child (6 months). Children appear to perceive international differ­ences before differences in phonetic segments, discriminating intonational rise and fall contours in adult English speech by 8 months. In terms of production, by 8 months distinctive intonational contours of rise and fall can be detected in child's output. They often signal differences in meaning.

The order of acquisition of classes of sounds goes by manner of articulation: nasals (/m/ first), then stops, liquids, fricatives and affricates. Classes characterized by place of articulation also appear in a certain order: (bi)labials, velars, alveolars and palatals. Thus the first consonants are /b, m, d, k/, the first vowels are /a, i/, the first syllables are of the consonant-vowel type (CV), the basic rhythm is syllabic.

All the children go through the stages of babbling, then one-word period, then constructing sentences (telegraphic style).

The general rule is that child's perception goes ahead of production: at first the child can distinguish more sounds than he/she can pronounce.

The critical period for language acquisition is from birth to puberty during which time a child must be exposed to human speech communication.

In second language learning there seems to be also the critical age after which the pronunciation of the target language is difficult to acquire. The time is uncertain but experiments suggest that every year counts.

Acoustic analysis is a method of speech signal processing. We can observe and take measurements of the waveform on display. We can see acoustic patterns corresponding to each class of sounds. Vowels are periodic sounds, and fricatives are aperiodic. Acoustic spectral analysis gives the picture called spectrogram with frequency bands representing energy distribution. For vowels Formant 1 (Fl) corresponds to the open/close dimension; Formant 2 (F2) corresponds to the front/back dimension.

Prosodic analysis is carried out along the parameters of fundamental frequency (F₀), intensity (Int), duration (T). Speech analysis and synthesis are two basic ways to explore speech sounds. Applied phonetics is used in education, health service, communication, aviation and other industries.

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