Introduction to phonetics

COMDIS 210: Survey of Communication Disorders

Definition of phonetics (Shriberg & Kent, 1982)

• The study of the perception and production of speech sounds (phonemes).

• The study of how speech sounds are produced and what their acoustic properties are.– Articulatory phonetics (concerned with how

sounds are formed)– Acoustic phonetics (concerned with the acoustic

properties of sounds)

• Clinical phonetics involves the application of articulatory and acoustic phonetics to the study of speech sound (articulation and phonological) disorders.

Phonemes

• The smallest linguistic unit of sound that conveys meaning.– One phoneme can change the entire meaning of a

word. (e.g., bat, ham, cars, ran)

• “Speech sounds”

• Includes consonants, vowels and diphthongs

• Every language has a specific number of phonemes that are used.

• SAE uses about 40-44 phonemes – 25 consonants– 15 vowels & diphthongs

• Phonotactics: the rules defining permissible sequences of phonemes to form meaningful words.– Each language has its own set of phonotactic rules.

The 3 major categories of phonemes

• Vowels

• Diphthongs

• Consonants

– Virgules (slashes) used to distinguish phonemes from letters.

International Phonetic Alphabet(IPA)

• Universal symbol system for classifying phonemes.

• Each phoneme is represented by a single symbol from the IPA.

• The IPA is a phonetic alphabet the describes and classifies each speech sound on the basis of how and where it is produced in the speech mechanism.

Vowels

• A vowel is a speech sound that is formed without a significant constriction of the oral and/or pharyngeal cavities, and that serves as a syllable nucleus.

• The position of the tongue distinguishes among almost all of the vowels in our language.

The tongue

• Muscular organ with no internal skeleton.

• Receives skeletal support from the mandible and hyoid bone.

• Divided into 5 parts:

The 5 parts of the tongue

• Body (mass or bulk of tongue)– Position important to description of vowels

• Tip (“apex”; visible when tongue protruded between the lips)– Used in over 50% of consonant contacts

• Blade (located behind the tip and in front of the dorsum. )

• Dorsum (back of tongue)

• Root (long segment forming the front wall of the pharynx; reaches down from the dorsum to the epiglottis and larynx)

Articulatory features of vowels

1. High/Low (represents tongue height)– vowels produced near hard palate = high vowels – vowels produced w/tongue depressed in mouth=

low vowels– Also can have mid-high, mid and mid-low vowels

“heat – hat--hoot – hop”“meat—mit—mate—met--mat”

IPA symbols for vowelsArticulatory characteristics of vowels

• Table 9.1 (p. 288)

2. Front/Back/Central (represents tongue advancement)

3. Rounded/Unrounded (represents whether lips are rounded or unrounded)

4. Lax/tense (represents the feature of tenseness/degree of muscle activity involved)

• Tense vowels have a longer duration than lax vowels.

The vowel quadrilateral

• A diagram depicting the tongue positions of vowels.– Tongue positions for vowels are specified as

points falling on the sides of, or within, the quadrilateral.

• The quadrilateral has at its corners /i/ (high-front), /u/ (high-back), /ae/ (low-front) and /XXX/ (low-back).

Diphthongs

• Monophthong: “pure vowel”; a vowel having a single, unchanging sound quality.

• Diphthong: vowel-like sound produced with a gradually changing articulation and resulting in a complex, dynamic sound quality. – Represented by a digraph (pair of symbols)– Has “on-glide” and “off-glide” segments

Phonetic transcription of words using selected vowels or diphthongs

1. sat2. sit3. seat4. suit5. set6. safe7. sign

8. soy9. sock10. saw11. life12. home13. sound14. soy15. town16. fame

Consonants

• A consonant is a speech sound that is produced with a significant constriction of the oral and/or pharyngeal cavities.

• Consonants , vowels and diphthongs can occur in the initial, medial and/or final positions of words.

• The number of possible consonant sounds exceeds 100. The English language uses about 25.

• Consonants are classified by their place of constriction, the manner in which they are produced and whether they require voicing.

• Different consonants are produced by changing either place, manner and/or voicing.

Ways of categorizing consonants(3 dimensions of consonant articulation)

• Place

• Manner

• Voicing

PLACE of articulation

• Phonemes are classified according to the PLACE where the articulatory constriction occurs. – “WHERE” the sound is formed

• Labials/bilabials (lips)– /p, b, m, w/

• Dentals (teeth)– /XXX,XXX)

• Labiodentals (lips and tongue)– /f,v/

• Alveolars (alveolar ridge)– /t, d, n, r, s , l/

• Glottals (glottis)– /h,w/

• Velars (velum)– /k, g, XXX/

• Palatals (hard palate)– /XXX, XXX, XXX, XXX, l)

MANNER of articulation

• Phonemes are classified according to HOW the articulatory constriction is created.– “How” the sound is formed.– How the airflow is constricted by the articulator.

Table 9.2, p. 289

• Stops (plosives)– Airflow completely stopped (air pressure built) in

the vocal tract before being released in a quick, explosive burst.

• Fricatives– Airflow is continuous but forced through a tiny

fissure in the vocal tract

• Affricates (stop + fricative)– Airflow completely stops (air pressure built) and

then released in a continuous stream through a tiny fissure in the vocal tract.

• Nasals– Airflow channels through the nasal cavity due to

closure of the velopharyngeal port

• Glides– Articulators glide from a constricted to a more

open position.– Also called “semi-vowels”

• Liquids– Tongue held tight at midline with openings

laterally; air flows around the sides of the tongue

Voicing

• Phonemes are classified according to whether or not they are created via vocal fold vibration.

• Voiced– All vowels; all diphthongs– Consonants (see. p. 289)

• Voiceless

Voiced sounds

• Phonemes that are created via vocal fold vibration.

• All vowels are voiced.

• All diphthongs are voiced.

• Some consonants are voiced.

Additional classifications

• Obstruents– Any sound formed with either a complete or

narrow constriction of the vocal tract.– Stops, fricatives, affricates

• Sonorants– Any sound formed without turbulent airflow (or

significant constriction) in the vocal tract.– Vowels, diphthongs, nasals, glides, liquids

• Allophone– Phonetic variant of a phoneme– If each phoneme represents a “family of sounds” ,

an allophone is one member of that family.