2 B Cues for consonants

Page 1

  • Perception of consonants in normal hearing

    • Focus on major and minor cues for identifying features of speech sounds.

    • Types of sounds discussed: stops, fricatives, affricates.

    • Presenter: Sejal Gunjal, Guided by: Dr. Sharda Sarda

Page 2

Introduction to Speech Sounds

  • Speech Sounds: Rapid fluctuations in air pressure generated by vocal organs.

  • Air Movement: Creates acoustic energy, causing listener's eardrum to vibrate.

  • Transformation: Acoustic energy → Mechanical energy → Neural energy leading to sound perception in the brain.

Page 3

Classification of Speech Sounds

  • Types of Speech Sounds:

    • Vowels

    • Consonants

    • Consonants: Articulated with complete or partial vocal tract closure.

    • Consonants vs Vowels: More complicated acoustic characteristics, can involve oral and nasal sound transmission.

    • Groups of Consonants:

      • Stops

      • Fricatives

      • Affricates

      • Nasals

      • Glides

      • Liquids

Page 4

Phoneme Classification

  • Phonemes: Consonants, Vowels

    • Sonorants: Continuous airflow

    • Obstruents: Stoppage or obstruction of airflow

Page 5

Types of Sonorants

  • Data on Sonorants:

    • Nasals

    • Approximants (semivowels)

    • Laterals

    • Glides

    • Liquids

    • Trills

    • Taps

Page 6

Types of Obstruents

  • Data on Obstruents:

    • Stops

    • Fricatives

Page 7

Classification of English Consonants

  • Stops: /p, b, t, d, k, g/

  • Fricatives: /f, v, θ, ð, s, z, ∫, Ʒ, h/

  • Affricates: /t∫, dƷ/

  • Nasals: /m, n, ŋ/

  • Glides: /w, j/

  • Liquids: /l, r/

Page 8

Features of Speech Consonants

  • Place of Articulation

  • Manner of Articulation

  • Voicing: Examples of voicing feature in stops and fricatives.

Page 9

Distinctive Features

  • Manner of Articulation: How consonant is articulated.

  • Place of Articulation: Where obstruction occurs in vocal tract.

  • Phonation: Voiced vs voiceless based on vocal cord vibration.

Page 10

Additional Features

  • Voice Onset Time (VOT): Timing of phonation after release of plosive.

  • Air Stream Mechanism: Most languages use pulmonic sounds.

  • Articulatory Force: Involves muscular energy in speech sound production.

Page 11

Understanding Stops

  • Essential Feature: Momentary blockage of the vocal tract.

  • Blockage Types: Articulatory occlusion; varies by language.

Page 12

Classification of Stops

  • Forms of Stops:

    • Transition

    • Aspirated

    • Release Noise Burst

    • Closure Characteristics

Page 13

Prevocalic Stops

  • Characteristics: Closure and release phase variability.

  • Energy Dynamics: Closure phase minimal energy; burst produced upon release.

Page 14

Aspiration of Stops

  • Aspiration: A breathy noise following the release burst.

  • Voicing Mechanics: Difference in voicing based on stop type.

Page 15

Acoustic Features of Stops

  • Perception Events: Transient, Friction interval, Voicing onset.

Page 16

Silence and Stop Consonants

  • Observation: Closure gap present before release of stop consonants (specific examples).

Page 17

Stop Gaps

  • Characteristics: Silent or near-silent intervals in voiced/voiceless stops.

Page 18

Identifying Stop Gaps

  • Acoustic Interval: Difference between voiced and voiceless stops defined.

Page 19

Burst Dynamics in Stops

  • Release Characteristics: Stops have rapid burst onsets.

Page 20

Stop Release Variations

  • Release Features: Transition to frication and measures of release duration.

Page 21

Spectral Data on Bursts

  • Energy Concentration: Bilabials, Alveolars, and Velars examined for acoustic characteristics.

Page 22

Voice Onset Time (VOT) Explained

  • Concept: Defines the timing between the transient and voicing.

Page 23

Range of VOT

  • Classification of VOT: Prevoicing, simultaneous voicing, short/long lag.

Page 24

Acoustic Studies on VOT

  • Observational Findings: Differences in VOT across bilabials, alveolars, and velars.

Page 25

Voicing and Stops

  • Characteristics: Distinguishing voiced and voiceless stops and their cues.

Page 26

Voicing Contrast Parameters

  • Factors: Voicing presence, duration, burst energy comparisons.

Page 27

Aspiration Characteristics

  • Insight into Aspiration: Patterns in voiceless versus voiced stops.

Page 28

Formant Transitions

  • Concept: Transition from consonant to vowel significant for speech perception.

Page 29

Vowel Duration and Stops

  • Vowel Characteristics: Differences in duration preceding voiced vs voiceless stops.

Page 30

Cues for Perception of Stops

  • Understanding Perception: Acoustic cues used by listeners related to stops.

Page 31

Major Differences of Stops

  • Differences from Other Sounds: Complete occlusion and momentary cessation of airflow as distinguishing features.

Page 32

Acoustic Cues in Stops

  • Important Factors: Silence, burst, and transitions aiding perception in noise conditions.

Page 33

Perceptual Confusion Studies

  • Findings: Confusion analysis of stops due to overlapping acoustic cues.

Page 34

Locus Theory and Place of Articulation

  • Theory Insights: Relationship between consonant-vowel combinations and F2 transitions.

Page 35

Two-Formant Perception Patterns

  • Research Findings: Importance of F2 transitions for distinguishing consonant perception.

Page 36

Voicing Differences in Stops

  • Nuances in Voicing: Multiple acoustic cues for redundancy in speech perception.

Page 37

Envelope Property of Sounds

  • Concept: Changes in overall envelope amplitude contour over time.

Page 38

Airflow Constriction Differences

  • Comparison: Various articulations affecting sound envelopes and constriction levels.

Page 39

Understanding Fricatives

  • Definition: Characterized by narrow constriction leading to turbulent noise.

Page 40

Classification of Fricatives

  • Categories: Nonstridents vs Stridents.

Page 41

Distinction among Stridents

  • Noise Energy: Intense versus less intense noise characteristics.

Page 42

Comparison of Stridents

  • Intensity Levels: Contrasting sound volumes and pitches.

Page 43

Perception Cues for Fricatives

  • Fricative Acoustic Cues: Features used to identify different fricatives.

Page 44

Manner of Fricative Articulation

  • Identification Mechanism: Use of spectral and amplitude features.

Page 45

Alveolar Fricatives

  • Production Techniques: Generation of noise energy by tongue positioning.

Page 46

Acoustic Properties of Alveolar Fricatives

  • Characteristics of /s/ and /z/ with respect to noise and frequency.

Page 47

Palatal Fricatives

  • Comparative Analysis: Distinct characteristics and noise energy levels.

Page 48

Nonstridents’ Features

  • Weak Energy Characteristics: Explain the nature of sound in this category.

Page 49

Overview of Linguadental Fricatives

  • Production Differences and Energy Characteristics

Page 50

Fricatives Perception Cues

  • Explanation of Fricative Identification: Noise and spectral properties crucial to perception.

Page 51

Distinction between Sibilants and Non-Sibilants

  • Distinction Mechanics: Identifying between dense and diffuse spectra effects.

Page 52

Listener Sensitivity to Voicing Class

  • Perception Cues: Importance of formant transitions and phonation presence.

Page 53

Overview of Nasal Consonants

  • Definition: How nasal consonants are produced by occluding oral tract and lowering the velum.

Page 54

Specific Nasal Production Characteristics

  • Detailed Articulation: Forming resonances through nasal passages defined for each nasal sound.

Page 55

Velar Port and Resonance

  • Nasal Sound Propagation: How sound travels through the nasals.

Page 56

Frequency Alterations in Nasals

  • Spectrum Damping: Influence of nasal cavities on upper formants.

Page 57

Features of Nasal Consonants

  • Common Acoustic Properties: Discusses the first formant and characteristics in perception.

Page 58

Acoustic Properties of Nasal Consonants

  • Key Features: Resonance characteristics and transition cues established.

Page 59

Place of Articulation Cues

  • Characteristics of Frequencies: How the transitions for different nasals vary based on articulation.

Page 60

Antiresonance Characteristics

  • Frequency Bettween Nasals: Comparison and identification mechanisms in perception study.

Page 61

Cues for Manner of Articulation in Nasals

  • Identification Techniques for Nasals: Variation in resonance and vowel impacts.

Page 62

Overview of Affricate Consonants

  • Definition and Types: Specific affricates in English highlighted.

Page 63

Acoustic Parameters of Affricates

  • Combined Characteristics of Sound Production: Transition from stop to fricative qualities defined.

Page 64

Perception Cues for Affricates

  • Sound Recognition: How silence, transient bursts, and other features aid in affricate identification.

Page 65

Acoustic Cues for Syllable Positioning

  • Critical Duration Analysis: Cues differ between affricate positions, emphasizing the role of acoustic features.

Page 66

Duration of Frication in Affricates

  • Experiments on Voice Distinction: Analysis of affricate perception based on frication duration effects.

Page 67

References

  • A list of references used for further reading and acknowledgment of sources.