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Exam Question Checklist

Exam 1997 Question 1

"Explain what is meant by 'resonance' in terms of the acoustics of the vocal tract. Describe how the source-filter model of speech production can be applied to explain the acoustic characteristics of diphthongal vowels and fricatives."

20 things you should mention:

  • Resonance
    • resonance is preferred frequency or preferred mode of vibration
    • characteristic of physical system, related to physical properties of system
    • vocal tract is physical system, shaped like acoustic tube
    • resonances in tube arise from standing waves
    • vocal tract resonances called formants
    • diagram: typical frequency response graph
  • Source-Filter Diphthongs
    • source x filter = output
    • digram: source spectrum
    • diagram: filter response
    • spectrum axes: amp & freq, response axes: response & freq
    • Characteristics of diphthongs: F1/F2 most important
    • Relate F1/F2 frequencies to tongue position
    • Moving tongue position -> moving resonances
  • Source-Filter Fricatives
    • Source of noise in constriction
    • or at obstacle
    • diagram: source spectrum
    • diagram: response of anterior cavity
    • main characteristic = freq of main peak
    • and bandwidth of peak
    • higher frequency/wider bandwidth as place fronted

© 2000 Mark Huckvale University College London