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Exam 1998 Question 5

" Explain the statement: "information about the identity of a consonant can be found in the adjoining vowel". Discuss the extent to which phonetic information about consonant place is encoded in an invariant sound."

20 things you should mention:

  • Identity
    • articulation is smooth and continuously changing
    • from target position from consonant to target for vowel
    • articulatory path at any instant affected by both current segment and neighbouring segments
    • response of v.t. and hence shaping of excitation affected by articulatory shape
    • spectrographic pattern changes as articulation changes
    • in particular major resonances move (formant transitions)
    • for segments such as plosives, the formant transitions depend on the place of the stop
      • and on the quality of the adjoing vowel
    • therefore the transitions give us an indication of consonant identity
    • diagram
  • Invariance
    • consonant place is partially defined by characteristic of segment itself
      • e.g. burst / frication shape / nasality
    • and the formant transitions into the adjoining vowel
    • vowels are relatively invariant sounds
      • but can be affected by e.g. lip rounding or nasality
    • transitions are sensitive to the position of vowel formant frequencies
    • thus formant transitions for e.g. /d/ are different across vowels
    • diagram
    • consistent property is locus frequency
    • namely where all transition appear to arise

© 2000 Mark Huckvale University College London