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