ACOUSTIC AND AUDITORY SPEECH MECHANISM

Dr. Elena ShapaLecture#3

February 14, 2012

Oral vs Written Speech Characteristics

• Oral speech is:• Spontaneous• Needs time• Is heard

• Written speech is:• Planned• Needs space• Is seen

Oral vs Written Syntactic Speech Units

• Oral Speech Units are:

TEXT SUPRAPHRASAL UNIT PHRASE

SYNTAGM

PHONETIC WORD SYLLABLESOUND

• Written Speech Units are:

TEXT PARAGRAPH SENTENCE

CLAUSE PHRASE

WORD MORPHEME

Oral Speech Syntactic UnitsIn oral speech the hierarchy of syntactic units from the largest to the smallest unit is the following:

TEXT SUPRAPHRASAL UNIT PHRASE SYNTAGM PHONETIC WORD SYLLABLE SOUND

A sound may be generally characterized by pitch, loudness, and quality.A syllable is a basic unit of written or spoken language consisting of a single uninterrupted sound formed by a vowel, diphthong, or a syllabic consonant alone, that can be used to make up words.A phonetic word is a unit of spoken language, where primary stress functions as its nucleus (see rhythmic group).A syntagm is a syntactic unit, a part of a phrase which represents a semantic and intonation entity in spoken language.A phrase is a syntactic structure of spoken speech that consists of more than one word but lacks the subject-predicate organization of a clause.A supraphrasal unit comprises a number of utterances independent structurally and semantically, united by one theme.

1. Segmental units are sounds of speech (vowels and consonants) which form the

vocalic and consonantal systems2. Suprasegmental, or prosodic, units are syllables, accentual (rhythmic) units, intonation groups, utterances, which form the subsystem

of pitch, stress, rhythm, tempo, pauses.

Units of Phonetics

The Sound Phenomena have Different Aspects:

• (a) the articulatory aspect;• (b) the acoustic aspect;• (c) the auditory (perceptive) aspect;• (d) the functional (linguistic, social) aspect –

phonology.

Speech Chain

Speaker's brain

Speaker's vocal tract

Transmission of sounds through

air

Listener's ear

Listener's brain

1 2 3 4 5

linguistic articulatory acoustic auditory linguistic

Correlation of Phonetic Terms articulatory characteristic

s

acoustic properties

auditory (perceptible)

qualities

linguistic phenomena

vibration of the vocal cords

fundamental frequency

melody pitch

different positions and

movements of speech organs

formant frequency

quality (timbre) phoneme

the amplitude of vibrations

intensity loudness stress

the period of time during which the

sound is pronounced

duration lengthtempo, rhythm,

pauses

Levels of the Language Phonetic Structure

• segmental phonemes represented by allophones

• syllabic structure of words

• accentual structure of words

• intonational structure of utterances

Articulatory Aspect

All the movements and positions of the speech organs necessary to pronounce a speech sound constitute its articulation.

The Speech Organs

• (1) power mechanism;• (2) vibration mechanism;• (3) resonator mechanism;• (4) obstruction mechanism.

Acoustic AspectThe basic vibrations of the vocal cords over their

whole length produce the fundamental tone of voice.

The simultaneous vibrations of each part of the vocal cords produce partial tones (overtones)

The number of vibrations per second is called frequency.

Frequency of basic vibrations of the vocal cords is the fundamental frequency.

Acoustic Aspect (2)

Pitch is the degree of highness or lowness varying with the number of vibrations of a

note. Speech melody – variations in the pitch of the

voice in connected speech.Duration of speech sounds is measured in

milliseconds .

Acoustic Properties

• Frequency• Intensity (decibels (dbs)) • Duration (milliseconds (msecs)) (length or

quantity of time during which the same vibratory motion is maintained)

• Voice-tamber or timbre (quantity and intensity of the overtones)

ACOUSTIC PHONETICS• Acoustic phonetics deals with the manner in which the

spoken message is encoded in the sound waves. According to the generally accepted source-filter theory of speech acoustics, sound is generated at a source (which for phonated speech is constituted by the vibrating vocal folds) and passed through the vocal tract.

• The opening and closing of the vocal folds create a succession of condensations and rarefactions of air molecules—variations in air pressure—and transform kinetic energy into acoustic energy. The sound wave generated at the glottis can be considered, for practical purposes, a complex periodic wave, and as such it contains energy at frequencies that are multiples of the fundamental frequency (harmonics).

Formants

• The vocal tract acts as a filter, transmitting more energy at those frequencies that correspond to the resonances of the vocal tract than at other frequencies. Energy concentrations at the resonance frequencies of the vocal tract are referred to as formants.

• In principle, the source and filter are independent of each other; consider the fact that the same vowel can be sung at different fundamental frequencies (pitches), and different vowels can be produced at the same pitch. The sound wave can be described by specifying its fundamental frequency, amplitude, and spectrum.

Acoustic Aspect

• Acoustic phonetics is a study of physical aspects of speech sounds.

• Speech goes away as the speech sounds come out of your mouth unless you record the speech. Thus, we record speech sounds for analysis. Acoustic phonetics includes study of fundamental frequency (pitch), amplitude/intensity (loudness), duration (length), formant estimates, and other physical aspects of speech sounds.

Functions of Speech Sounds

• Constitutive function • Distinctive function• Recognitive function

Distinctive function• on the level of the word-form (ask-

asked)• on the level of the word (dreamer-

dreamy)• on the level of the sentence (It was cold.-It was gold)

Functional Aspect

From the purely linguistic point of view these abstractions are called phonemes and their realizations in different positions are called allophones.

Phonology was founded by the Russian linguist I.A. Baudouin de Courtenay in the 2nd half of the 19th cent.

Functional Aspect

[t] - occlusive, forelingual, apical, alveolar, aspirated, voiceless fortis consonant

• Tea – slightly palatalized before front vowels• Sty – unaspirated• Little – pronounced with lateral plosion before

[l]• Written – pronounced with nasal plosion

before [n]

Reference Reference 1. Gimson A.C. An Introduction to the Pronunciation of English. London,

1972.2. Jones D. English Pronouncing Dictionary. 15th ed. CUP, 1997.3. Leontyeva S.F. A Theoretical Course of English Phonetics. M., 20024. Sokolova M.A., Gintovt K.P. English Phonetics. A Theoretical Course.

M., 1996.5. Vasilyev V.A. English Phonetics. A theoretical course. M., 1970.6. Соколова М.А. Теоретическая фонетика английского языка.

Практикум. М., 20037. Трубецкой Н.С. Основы фонологии. М., 1960.8. Шахбагова Д.А. Фонетическая система английского языка в диа-

хронии и синхронии (на мат-ле брит., ам., австрал., канад. вариантов англ. языка). М., 1992.

9. Шевченко Т.И. Социальная дифференциация английского произношения. М., 1990.

10. Gillian Brown. Listening to Spoken English. M., 1984.