Phoneme

• Smallest unit of speech
  • Distinguish words
• Continuous speech is stream of different phonemes
• English has 44
• Consonants
  • Voiced or unvoiced
• Vowels
  • All voiced

Voiced

• Quasi-periodic vibration of vocal cords
• Sound transmitted along vocal tract unimpeded
• Air forced through glottis
  • Quasi-periodic oscillation

Unvoiced

• Air flow through vocal apparatus is either cut-off or impeded
  • Constriction using tongue or lips
• Turbulence or noise
  • Fricatives
    • \s\, \f\
  • Plosives
    • \p\, \t\
• Modelled as random noise

Formant

• Vocal tract can be modelled as resonant system
• Modes or peaks in spectral response of resonant system
• Lowest 3 most important in speech