1. Source Filter Theory: Consonants
    • source=noise from the constriction
    • resonance based on whole vocal tract but cavity in front of constriction is most important
  2. the larger the front cavity.....
    the lower the first resonance frequency, more resonance shaping to the noise
  3. characteristics of antiformants
    • contribute to filtering for consonants
    • areas which are characterized by a loss of sound energy
  4. when are antiformants formed
    • vocal tract is constricted like in /s/
    • vocal tract is bifurcated like in /n/ (air passes through in two places as opposed to one
  5. what are the characteristics of glides
    • aka semivowels look like vowels in nature
    • articulatory motions appear like slowly changing formant pattern
    • transition for a glide is longer than for a stop but shorter than for a dipthong
    • because of short duration, may not reach a steady state - depends on f2/f3 transitions
  6. glides in comparison to vowels...
    • w=u
    • j=i
    • f1 f2 constriction is greater for glides so they appear lower than that of vowels
    • f3=
    •     weak for w
    •     higher for i than for j
  7. what do f1, f2, and f3 represent
    • f1=tongue height
    • f2=tongue advancement
    • f3=postion of tongue tip
  8. liquid chracteristics
    • l:
    •   great formant variability due to effects of
    •   vowel context

    • r:
    •    f3 is lower than for l, so close to f2
    •    distinctive acoustic property of r
    •    formants are influenced by position in
    •    word
  9. acoustic cues for stops
    • –Silent or low-energy period (stop closure, stop gap) 
    • –Burst
    • –Aspiration
    • –Transition
    • –Voicing cues (i.e., voice bar)
  10. characteristics of PREvocalic stops
    • syllable initial
    • closure (stop gap)
    • release (noise burst)-aspirated or unaspirated
    • transition (formant transition)
  11. characteristics of POSTvocalic stops
    • syllable final
    • transition (formant transfer)
    • stop closure (stop gap)
    • release (can either be a burst or no burst)
    • voicing is cued by vowel for postvocalic stops
  12. aspiration
    • breathy noise generated as air passes partially closed vfs and in pharynx
    • noise is glottal fricative
    • follows the burst
    • present for voiceless stops
  13. stop closure/gap
    • acoustical interval corresponding to articulator closure, it is identified on a spectrogram as an interval of relatively low energy and conspicuously lacking in formant pattern or noise (basically it is the portion of sound where we would not see any activity on spectrogram)
    • can be measured on a spectrogram
    • silent for voiceless stops, voicing may be present for voiced stops
  14. burst
    • the brief noise created during the release of a stop consonant
    • interval of noise due to friction as the constriction is released
    • stops can be determined by bursts alone
  15. when is a burst present
    usually for initial and medial stops, can be missing for final stops (unreleased)
  16. what does a burst show
    place of articulation information
  17. what is used to assess bursts
    • spectrums
    • bilabial: flat or falling spectrum, low freqs
    • alveolar: diffuse, rising spectrum, high freqs
    • velar: compact, mid freq spectrum
    • not always present for final stops
  18. formant transitions
    • the vocal tract configuration changes from the oral constriction for the stop to a relatively open shape for the following vowel
    • f1 is cue to manner of articulation
    • f2 and f3 transition are cues to place of articulation
  19. voice onset time and waveform
    • vot
    • scribbly lines at top of spectrogram important because shows amplitude changes in speech
    • larger portions=larger amplitude
    • useful in defining markers
    • interval between the release of the stop marked by burst and the onset of voicing
  20. what is vot affected by
    • suprasegmentals (speech rate, word stress, semantic importance, and utterance length)
    • norms based on single word production may not be the same as vot in natural speech because we do not speak in broken words
  21. semantic importance
    stress or intent of meaning when change in speech it is not natural speech
  22. development of vot
    • in infants-vot fall uniformly along the continuum
    • then vot of all stops cluster around voiced part of continuum
    • with development, voiceless sounds are associated with longer vot (adultlike by 7-8)
    • children have to learn delay voice onset
  23. fricatives
    • noise generated at site of constriction
    • unclear what acoustic characteristics are used for discrimination of fricatives 
    • varies based on following vowel
    • weak formant peaks
  24. afficates
    • distinguished by:
    • rise time of noise energy (time to max amp), stops most rapid, affric in middle, frics least rapid
    • duration of fric: shorter for affric
    • presence of release burst
    • duration of stop gap
    • temporal/spectral characteristics of preceding vowel
  25. nasal consonants
    • low formant freqs due to long cavity (nasal and oral cavities are coupled)
    • large bandwidths due to damping
    • antiresonances are present
  26. what is a nasal consonant dominated by
    • a low formant
    • lowest resonant freq in nasal murmur=nasal formant, has the highest amp of all resonances in the nasal murmur
  27. nasal consonant
    formant transitions
    place of articualtion
  28. what do listeners use to distinguish manner of artic for nasal
    vowel nasalization
Card Set
Consonant waves