Branches of phonetics and their interconnection.
Phonetics has branches of its own. First of all it is divided into special phonetics and general phonetics.
Special phonetics is concerned with the study of the phonetic structure of a particular language. It is subdivided into descriptive phonetics and historical phonetics.
Descriptive phonetics deals with the phonetic system of a particular language at a particular (mostly contemporary) period.
Historical phonetics aims at tracing and establishing the successive changes in the phonetic system of a given language at different stages of its development. It uses the philological method of investigation, which consists in studying written monuments and comparing different spellings of one and the same word. Historical phonetics is a part of the history of a language. But it is also important for the study of the modern phonetic system of a language because without a historical approach it is impossible to understand how this modern phonetic system came to be and what further changes it is likely to undergo. Historical phonetics is connected with general history, the history of the people whose language is studied and archeology.
General phonetics studies all the sound-producing possibilities of the human speech organs and the ways they are used for purposes of human communication by means of language, i.e. it finds out the types of speech sounds in different languages of the world, the way they are produced and the role they play in forming and expressing thoughts; it investigates the laws governing the changes of speech sounds in the flow of speech and finds out the types of such changes in various languages it determines the nature, types and role of other phonetic means necessary to convey thoughts in various languages, such as word accent, syllabic structure and intonation. General phonetics is a part of general linguistics.
General phonetics and special phonetics are closely interconnected. On the one hand general phonetics is based on the extensive material which the special phonetics of a great number of languages provides. It is also based on the achievements data of other sciences, such as physics, biology, psychology, speech pathology etc. As a result, general phonetics has been able to analyze phonetic phenomena from different points of view and to formulate a number of important theories: the phoneme theory, the theories of syllable formation and division, theories connected with syntagm, stress, intonation, graphical rules and rules of orthography etc. On the other hand, general phonetics provides valuable theoretical material which enables us to understand clearly and to interpret correctly the different phonetic phenomena of a concrete language.
Comparative phonetics investigates the phonetic system of two or more languages especially kindred ones, and find out the correspondences between the elements of phonetic system of these languages.
Phonetics is also divided into segmental phonetics, which is concerned with individual sounds and suprasegmental phonetics, which is concerned with the larger units of connected speech: syllables, words, phrases and texts where prosodic characteristics of speech are revealed.
The next division of phonetics into several branches is determined by the complex nature of speech sounds which manifests itself in four different aspects such as articulatory, physical, or acoustic, auditory and functional, or linguistic. Each aspect is studied by a certain branch of phonetics.
a). Articulatory phonetics. From the articulatory point of view every speech sound is a complex of definite, finely coordinated and differentiated movements and position of the various speech organs. All the movements and positions of the speech organs necessary to pronounce a speech sound constitute its articulation.
Organs of speech include the power mechanism, the vibrator mechanism, the resonator mechanism, the obstructer mechanism. The power mechanism consists of the diaphragm, the lungs, the bronchi, the windpipe (or trachea), the glottis, the larynx, the mouth cavity and the nasal cavity. The vibrator (or voice producing) mechanism consists of the vocal cords. The resonator mechanism consists of the pharynx, the larynx, the mouth cavity and the nasal cavity. The obstructer mechanism consists of the tongue, the lips, the teeth, the soft palate, the uvula, the hard palate, the alveolar ridge. The four mechanisms are not only closely interconnected, but actually also overlap, as the speech organs forming part of one mechanism may form at the same time part of another mechanism thus performing different functions. Each speech sound is the result of the simultaneous work of all the four mechanisms. From the point of view of their functions the speech organs of the obstructer mechanism are divided into active and passive. The active organs of speech are the vocal cords, the tongue, the lips, the soft palate with the uvula. The passive organs of speech are: the teeth, the teeth ridge, the hard palate, and the walls of the resonance chambers (or the supra-laryngeal cavities). The active speech organs are mobile; in articulating sounds they occupy one or more positions in respect to the passive organs of speech which are immobile.
So articulatory phonetics is concerned with the study, description and classification of speech sounds in the framework of their articulation and in connection with the organs of speech by which they are produced. It is connected with such non-linguistic sciences as physiology and anatomy.
b). Acoustic phonetics. From the physical, or more exactly, acoustic point of view a speech sound like any other sound in nature is a physical phenomenon and it is communicated to the air in the form of sound waves, which appears due to the disturbance of the air stream by the movements of the speech organs. These movements push the particles of air which are next to it and displace them. The displaced layer of particles displaces the next layer, and the pressure is transmitted through the air. Thus, the space between the air particles becomes smaller and the air is compressed or condensed. Compressed air particles reach the listener’s ear-drum and cause pressure to it. When the pressing force has spent itself, the displaced particles return to their original position because of the elasticity of air and produce rarefactions behind them – that is the space between two neighbouring particles is increased. These alternating waves of condensation and rarefaction are sound waves.
Sound waves have a number of physical properties, such as frequency, length, amplitude and duration, which all exist and manifest themselves simultaneously; each of them can be singled out and separated from the others only for purposes of analysis. Frequency is the number of vibrations per second. Sound waves may follow one another at different rates of frequency, therefore the number of vibrations, or cycles per second varies greatly. Length is the distance between the point of maximum compression in one wave to the point of maximum compression in the next wave, or, in other words the distance between points having the same phase (position) in two adjacent waves. Wave length is inversely proportional to the frequency of vibrations; the higher the frequency, the shorter the wave length. Frequency of repeated pressure on the ear-drum is perceived as the pitch of the sound. The greater the frequency, the higher the pitch, and vice versa. The frequency of sound depends on certain physical properties of the vibrator, such as its mass, length and tension. The greater the mass of the vibrator, the slower its vibrations, and the lower the pitch (other conditions being equal). Some people’s vocal cords are thicker and heavier than those of others and their voices are lower than the voices of those with thinner, lighter vocal cords. The longer the vibrator, the slower the vibrations, the lower the frequency and the pitch. A man’s voice is lower than a woman’s partly because his vocal cords are longer. As the tension of the vibrator increases, the frequency increases and the pitch rises. Amplitude of vibrations is the distance to which the air particles are displaced from their position of rest by the application of external force, produced by the movement of speech organs, or, in other words, by the degree of the condensation of air and therefore by the force of the pressure which the displaced air particles exert on the ear-drum. The amplitude of vibration is correlated with the intensity of the sound, changes in which are perceived primarily as variations in the loudnessof sound. Naturally, the greater the external force applied to cause vibration, the greater the amplitude of vibration, the greater the intensity of sound, the greater the pressure of the displaced air particles upon the ear-drum, the louderthe sound. Intensity is measured in decibels. Closely connected with the frequency and amplitude of sound is its composition or complexity. A physical body that is set into vibration vibrates not only as a whole but also in its parts (segmental vibrations). The sound wave produced by the vibration of the whole body is called the fundamental. Waves produced by the vibrations of the parts of the body are called partial waves.Most sound waves are complex ones i.e. they consist of the fundamental and partial waves blended together. The frequency of the fundamental wave is lower than that of the partial waves. The sound wave which results from the vibrations of the whole body and which has the lowest frequency is perceived as the fundamental tone. The characteristic partial waves which result from the vibrations of the parts of the vibrating body are perceived as partial tones, or overtones. They are perceived as changes in tambre. Like any other form of matter sound can only exist and develop, or move, in time. In other words, any sound has a certain duration. It can be defined as the quantity of time during which the same vibratory motion, the same patterns of vibration are maintained.
So acoustic phonetics studies all the above mentioned acoustic properties of speech sounds, the way in which the air vibrates between the speaker’s mouth and the listener’s ear. It is connected with such non-linguistic science as physics.
c). Auditory phonetics. From the auditory point of view speech sounds are perceived by the listener’s hearing organs and transmitted through the nervous system to the brain as a spoken message.
So auditory phonetics investigates the hearing process, caused by brain activity, the means by which we discriminate sounds, that is pitch, tamber, loudness, length of sounds, which are correlated with the physical properties of the corresponding sound waves. It is connected with such non-linguistic sciences as physiology, anatomy and psychology.
d). Functional phonetics (phonology, phonological phonetics). From the functional point of view speech sounds are significant units of the language which perform different linguistic functions, such as constitutive, recognitive and distinctive. In contrast to the greater language units, such as morphemes, words and sentences, speech sounds have no meaning by themselves. But a morpheme or a word can only exist in the form of a speech sound or a sequence of speech sound, and any modification of a word can be effected only on the basis of speech sound. Sentences as material forms of thoughts are, too although indirectly made up of definite sequences of speech sounds, whose order is determined by the order and grammatical form of words, used in them. Morphemes, words and sentences differ from one another, and are recognizable by interlocutor, which is also achieved due to the difference in speech sounds and their sequences.
So, functional phonetics deals with linguistically relevant or phonological (functional) properties of speech sounds, the properties which are essential for the communicative process.
Recently within functional phonetics sociophonetics has been singled out. It studies the ways in which phonetic structures interact with society and change in response to different social functions.
Functional phonetics is connected with such non-linguistic sciences as sociology and statistics.
The interconnection of articulatory, acoustic, auditory and linguistic aspects of speech sounds is observed in the succession of stages in the human speech production. First, the formation of the concept takes place in the brain of the speaker. The message formed within the brain is transmitted along the nervous system to the speech organs which articulate a particular pattern of speech sounds. The materialized sound waves have certain acoustic properties by which the listener’s auditory apparatus perceives them and the nervous system sends the message to the brain, where the linguistic interpretation of the information is conveyed.