Basic Spectrogram

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Basic Spectrogram Clinical Application
Consonants
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Sonarants

• Consonant that manipulates vocal tract resonance
• Characteristics
• F2 F3 formant changes
• Transitions
• Include
• Nasals /m/, /n/ /h/
• Liquids /r/, /l/
• Glides /w/, /j/

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Sonorants

• Production involves a greater constriction when
  compared to vowels and a quicker more extreme
  movement of the vocal tract compared to
  diphthongs
• Movements and formant transitions slower than all
  other consonants

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Nasals

• Low frequency energy (near Fundamental
  Frequency)- Nasal Murmer
• Place of nasal articulation is defined by the 2nd
  formant transition place of antiresonances

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m
n
a
a
Nasal Murmur
Spectrogram Nasals
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Glides

• Semivowels /j, w/
• Gradual transitions that appear on the
  spectrogram as a slowly changing formant pattern
• Formant transitions
• Duration 75-150 ms

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Spectrogram Glides
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Liquids

• Liquids /l, r/
• Formant pattern steady state and transition is
  the primary acoustic cue
• Prolongation effects
• /l/ steady state formants
• F1 360 Hz
• F2 1300 Hz
• F3 2700 Hz
• /r/ steady state formants
• Same F1 F2 as /l/ but much lower F3

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Spectrogram Liquids
l
r
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Stops

• Acoustic Cues Silent or low energy interval,
  burst, transition
• Silent interval oral constriction (I.e. closure
  of lips for /b/) also termed a stop gap
• Voiced stops can be seen on the voice bar as
  noise energy
• Burst Articulatory constriction is released
  energy released looks like noise on the
  spectogram
• Transition formant transition into following
  vowel

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Stops

• Bilabial Stops (/p/, /b/)
• F1 starts at zero rises to F1 of next vowel
• F2 starts at 800 Hz rises to F2 of following
  vowel
• F3 increases for following vowel
• Alveolar Stops (/t/, /d/)
• F1 same as for bilabial stops
• F2 starts at 1800 Hz rises to F2 of following
  vowel
• Velar Stops (/k/, /g/)
• F1 same as for bilabials
• F2 has 2 starting points 1300 2300 Hz

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Spectrogram with Transitions /d a d/
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Voiceless Stop Consonants
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Stops

• Characteristics
• Voice onset time (VOT) time between stop release
  (burst) and the onset of glottal pulsing
• Voiced shorter VOT
• Longer VOT in cleft palate, dysarthric speakers
  and phonological disorders

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Fricatives

• Spectrum of noise is the acoustic cue formant
  transition
• Specific location of turbulence
• Labiodental /f,v/
• Low energy, flat diffuse spectra (front cavity is
  short with little filtering effect on noise
  energy)
• Linguadental /q,ð/
• Low energy, flat and diffuse spectra (front
  cavity gives little shaping to spectrum)
• Lingu-alveolar /s, z/
• High energy noise spectra, energy lying in high
  frequencies (above 4 kHz) (front cavity longer
  contributing to distinctive spectral shaping)
• Linguapalatal /sh, zh/
• Intense noise spectra, energy lying in mid to
  high frequencies (above 2kHz) (front cavity
  significant resonance effect)

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Spectrum Changing Pattern of Fricative Noise
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Fricatives Spectrum
Higher energy spectra
Low to mid energy spectra
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Affricates

• Affricate consonants have a stop gap (silence,
  low energy interval) followed by intense
  frication
• Stop gap articulatory closure
• Frication noise after closure is released

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Spectrogram /judge/
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Laboratory

• Part I SONORANTS
• Nasal Consonants
• Make a wide-band spectrogram of
• mow, no
• Draw a vertical line where consonant ends and
  vowel begins
• Locate nasal murmer, 1st 2nd formants,
  antiresonances
• What spectral differences do you see?
• Locate the 2nd formant transitions on both. What
  are the differences?
• Some, Sun
• Label the same as the first spectrogram
• Contrast both spectrograms

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Laboratory

• Part II Approximants
• Glides Liquids
• Wide band spectrogram of a ray, a lay, a
  way, a yea
• Label each phone on the spectrogram
• Compare /r/ /l/
• Determine the relative frequency of F1, F2 F3
• Determine whether there is acoustic energy
  present at higher frequencies is low or high
• What acoustic characteristics are different
  between consonants?

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Laboratory

• Part III Silibants
• Fricatives
• Say sigh and shy at a moderate rate
• Obtain a wide-band spectrogram (at least 8 kHz)
• Locate label each phone
• What are the spectral characteristics that
  distinguish it from vowels and other consonants?

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Laboratory

• Part II Nonsilibnts
• Obtain a wide-band spectrogram of high, fie
  and thigh
• Label each phone
• What spectral features distinguish phones?
• How do they differ from silibants?
• Obtain a wide-band spectrogram of ether and
  either
• Label