Exam Question Checklist

Exam 1998 Question 1

"Explain how the spectrograph is able to produce an analysis of the frequency content of speech signals. Describe how you would use the spectrograph to study a speaker’s use of intonation in everyday speech and discuss what problems might arise."

20 things you should mention:

• Spectrograph
  • filterbank (or spectrum)
  • capture energy as output of band-pass filters
  • represent as grey scale (freq/time/amp)
  • wide-bandwidth filters or 300Hz
    • good temporal / poor frequency resolution
    • useful for pitch periods /formants
  • narrow-bandwidth filters or 45Hz
    • poor temporal / good frequency resolution
    • useful for harmonics
  • diagram(s)
• Recording
  • make recordings of a speaker in normal situation
  • transcribe recordings
  • add intonation marking (e.g. type & position of accents)
  • use narrow-band analysis to find Fx contour
  • relate Fx contour to prosodic transcription
  • relate prosodic transcription to circumstances of use
  • collect statistics on Fx
  • problem with audio quality
    • better to use Laryngograph
  • problem with interpretation of contours