SPSC2003 Acoustics of Speech and Hearing

Examination Preparation

Introduction

Use the information on these pages to help you prepare for the written examination. Below you will find the text of the B203 written examinations in 1997, 1998 and 1999. Note that B214 examination papers will be eerily similar. For each question, you should first try to create an outline answer, using your notes if you wish. If you want exam practice, you can then try to write the answer in full within 45 minutes. Once you have prepared your answer you should then and only then look at the list of 20 points that we think should be in your answer. You will not make the best use of this material if you cheat!


B203 Acoustics of Speech and Hearing 1997

3 hours

Answer FOUR questions. All questions are equally weighted.

  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-point checklist
  2. A central issue in speech perception is how listeners are able to give a reliable indication of the identity of a phonetic segment despite a great deal of variation caused by speaker, context and listening environment. Describe these three types of variability, giving examples. Discuss what information a listener might use to compensate for such variability. 20-point checklist
  3. Describe an experiment that might be used to investigate the hypothesis that the use of fundamental frequency by a speaker varies between formal and informal settings. Ensure your answer includes: subject selection, recording environment, recording equipment, signal analysis and interpretation of results. 20-point checklist
  4. A tape recorder is quoted as having a frequency response of 500Hz to 5000Hz within 3dB. Explain what this statement means. Describe the procedure by which the frequency response of this tape recorder might have been measured. Discuss the suitability of this tape recorder for recording speech. 20-point checklist
  5. Explain the difference between sound intensities measured in dBSPL and in dBHL. Describe the procedure by which a pure-tone audiogram is measured for a listener. Why is the ear more sensitive to pure tones with frequencies between 1000Hz and 4000Hz? 20-point checklist
  6. Write notes on ALL of the following: (a) speech pattern audiometry (50%) (b) creaky voice (25%) (c) harmonic synthesis (25%) 20-point checklist
  7. Outline the principles behind spectrographic analysis, discussing why both wide and narrow band filters are used to study speech signals. Contrast the filters used in the spectrograph to analyse speech with those supposed to operate in the cochlea. 20-point checklist
  8. Sketch stylised spectrograms of ‘bard' and ‘park' and list the acoustic cues that distinguish the initial and final consonants. Discuss how Voice Onset Time (VOT) varies between a) voiced and voiceless plosives b) bilabial, alveolar and velar plosives c) English and French plosives. 20-point checklist


B203 Acoustics of Speech and Hearing 1998

3 hours

Answer FOUR questions. All questions are equally weighted.

  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-point checklist
  2. Frequency response graphs are useful for the description of systems. Explain how they may be used to: (i) assess the quality of audio equipment; (ii) explain the acoustics of speech production. 20-point checklist
  3. Describe how the Laryngograph operates. Relate characteristics of the Laryngograph signal to the actions of the vocal folds in modal, creaky and falsetto voice. 20-point checklist
  4. Use the model of the speech chain to discuss the processes involved in the communication of the identity of a phonological vowel (e.g. /æ/ in ‘cat’) from speaker to hearer. 20-point checklist
  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-point checklist
  6. Explain how Voice Onset Time (VOT) varies across voiced and voiceless plosives in English and in one other language. Briefly describe an experiment to confirm that perception of VOT matches production of VOT in these two languages. 20-point checklist
  7. How is the perceived loudness of pure tones related to their intensity and frequency? How does the perceived loudness of pure tones differ for listeners with a cochlear hearing loss? 20-point checklist
  8. Write short notes on ALL of the following: a) place coding of frequency; b) masking; c) beats. 20-point checklist


B203 Acoustics of Speech and Hearing 1999

3 hours

Answer FOUR questions. All questions are equally weighted.

  1. Describe the acoustics of fricative production. Contrast the different characteristics of: a) the glottal fricative; and b) sibilant fricatives; and c) dental or labio-dental fricatives. 20-point checklist
  2. Describe in detail the auditory and perceptual stages involved in determining the phonological identity of a vowel sound. 20-point checklist
  3. Use the analogy of a bank of filters to describe how the spectrograph analyses speech signals. What is the difference between wide-band and narrow-band analysis? Which type of analysis is preferred for measuring formant frequencies and why? 20-point checklist
  4. Explain what is meant by the frequency response of a system. Describe an experiment in which the frequency response of a simple resonator is measured. How is the bandwidth of a simple resonator related to the rate of energy lost from the resonator during vibration? 20-point checklist
  5. What is meant by locus frequency? How does locus frequency information aid the listener in identifying consonants? How can the sensitivity of listeners to locus frequency be established by an experiment? 20-point checklist
  6. Describe how distributions of fundamental frequency use may be obtained from laryngographic analysis. Discuss the problems of obtaining a reliable indication of fundamental frequency range from laryngographic analysis. Discuss the relative advantages of the laryngograph over narrow-band spectrograms for the study of intonation contours. 20-point checklist
  7. Describe what equipment and what method you would use to make the following measurements: a) the measurement of the intensity of a sound using the dBSPL scale; and b) the measurement of hearing impairment for pure tones using the dBHL scale: and c) the measurement of the perceived loudness of a pure tone using the phon scale. 20-point checklist
  8. List TEN things to check for when making speech recordings designed for acoustic analysis. In each case discuss the potential consequences of NOT following your advice. 20-point checklist