COMD 5070 LATEST 2026 EXAM QUESTIONS AND
SOLUTIONS RATED A+
✔✔sampling rate - ✔✔is how often you take a snapshot, it is in Hz, 10 samples per
second = 10 Hz
✔✔Why are speech acoustic measures limited in how well they reflect specific speech
movements in the vocal tract? - ✔✔acoustic patterns reflect vocal tract movements with
some ambiguity, motor equivalence: the same sound can be produced several ways,
acoustics cannot reveal all details of movement
✔✔What is high speed imaging? - ✔✔is real life slow motion version of filming
✔✔stroboscopy - ✔✔is a simulation (or optical illusion, animation) of a slow motion of
the vocal folds [the fundamental frequency must be steady for the timing to work
otherwise it will be blurry]
✔✔types of vocal perturbation - ✔✔jitter and shimmer
✔✔jitter - ✔✔when each successive cycle deviates from this 10 millisecond average by
a tiny amount (a few microseconds) these differences are what we call jitter. So jitter is
a frequency perturbation [jitter = frequency perturbation]
✔✔shimmer - ✔✔is a random cycle-to-cycle difference in amplitude [shimmer =
amplitude perturbation or amplitude instability]
✔✔perceptual voice quality: a hoarse voice is: - ✔✔higher in perturbation
✔✔perturbation sounds: - ✔✔rough and hoarse, there is a very rapid and random
change [wobbley, scratchy]
✔✔modulation sounds: - ✔✔rhythmic sounding and predictable (not random) [like an
opera singers voice]
✔✔how does a electroglottograph receive information? - ✔✔two electrodes are placed
on either side of the neck, over the thyroid laminae, and a small current is passed
through
✔✔there is more current when: - ✔✔the vocal folds are together
✔✔there is less current when: - ✔✔the vocal folds are open
✔✔what does an electroglottograph show? - ✔✔it records the vocal fold contact area,
and changes in the vocal fold adduction
, ✔✔on a spectrogram the x and y axes represent, respectively - ✔✔time, frequency
✔✔a single vertical line on a line spectrum would represent - ✔✔a sine wave
✔✔a low pass filter - ✔✔blocks high frequencies
✔✔loudness is best measured by - ✔✔having a listener make a perceptual judgement
✔✔when a signal is converted from analog to digital form, the number of 'snapshots' per
second is the - ✔✔sampling rate
✔✔a simple, low tech tool for a doctor to view a person's larynx is - ✔✔a laryngeal
mirror
✔✔in vocal modulation, the frequency changes over time are - ✔✔slow and rhythmic
✔✔an electroglottograph reveals details of voicing by: - ✔✔passing a current across the
vocal folds
✔✔the best way to avoid aliasing during a digital recording is to use a - ✔✔low pass
filter
✔✔if it's not harmonic it is - ✔✔noise
✔✔amplitude vary in - ✔✔how big they are
✔✔phase angles vary in - ✔✔where they are at in their cycle relative to one another
✔✔frequencies vary in - ✔✔there are many different ones to choose from
✔✔harmonics are - ✔✔multiples of the fundamental
✔✔each peak in a FFT spectrum is - ✔✔a harmonic
✔✔wavelength is calculated by: - ✔✔the speed of sound is divided by the frequency of
the sound wave. Frequency = speed/wavelength
✔✔what an object is made of affects: - ✔✔the speed of the sound wave
✔✔the length of the object affects: - ✔✔the wavelength of the sound wave
SOLUTIONS RATED A+
✔✔sampling rate - ✔✔is how often you take a snapshot, it is in Hz, 10 samples per
second = 10 Hz
✔✔Why are speech acoustic measures limited in how well they reflect specific speech
movements in the vocal tract? - ✔✔acoustic patterns reflect vocal tract movements with
some ambiguity, motor equivalence: the same sound can be produced several ways,
acoustics cannot reveal all details of movement
✔✔What is high speed imaging? - ✔✔is real life slow motion version of filming
✔✔stroboscopy - ✔✔is a simulation (or optical illusion, animation) of a slow motion of
the vocal folds [the fundamental frequency must be steady for the timing to work
otherwise it will be blurry]
✔✔types of vocal perturbation - ✔✔jitter and shimmer
✔✔jitter - ✔✔when each successive cycle deviates from this 10 millisecond average by
a tiny amount (a few microseconds) these differences are what we call jitter. So jitter is
a frequency perturbation [jitter = frequency perturbation]
✔✔shimmer - ✔✔is a random cycle-to-cycle difference in amplitude [shimmer =
amplitude perturbation or amplitude instability]
✔✔perceptual voice quality: a hoarse voice is: - ✔✔higher in perturbation
✔✔perturbation sounds: - ✔✔rough and hoarse, there is a very rapid and random
change [wobbley, scratchy]
✔✔modulation sounds: - ✔✔rhythmic sounding and predictable (not random) [like an
opera singers voice]
✔✔how does a electroglottograph receive information? - ✔✔two electrodes are placed
on either side of the neck, over the thyroid laminae, and a small current is passed
through
✔✔there is more current when: - ✔✔the vocal folds are together
✔✔there is less current when: - ✔✔the vocal folds are open
✔✔what does an electroglottograph show? - ✔✔it records the vocal fold contact area,
and changes in the vocal fold adduction
, ✔✔on a spectrogram the x and y axes represent, respectively - ✔✔time, frequency
✔✔a single vertical line on a line spectrum would represent - ✔✔a sine wave
✔✔a low pass filter - ✔✔blocks high frequencies
✔✔loudness is best measured by - ✔✔having a listener make a perceptual judgement
✔✔when a signal is converted from analog to digital form, the number of 'snapshots' per
second is the - ✔✔sampling rate
✔✔a simple, low tech tool for a doctor to view a person's larynx is - ✔✔a laryngeal
mirror
✔✔in vocal modulation, the frequency changes over time are - ✔✔slow and rhythmic
✔✔an electroglottograph reveals details of voicing by: - ✔✔passing a current across the
vocal folds
✔✔the best way to avoid aliasing during a digital recording is to use a - ✔✔low pass
filter
✔✔if it's not harmonic it is - ✔✔noise
✔✔amplitude vary in - ✔✔how big they are
✔✔phase angles vary in - ✔✔where they are at in their cycle relative to one another
✔✔frequencies vary in - ✔✔there are many different ones to choose from
✔✔harmonics are - ✔✔multiples of the fundamental
✔✔each peak in a FFT spectrum is - ✔✔a harmonic
✔✔wavelength is calculated by: - ✔✔the speed of sound is divided by the frequency of
the sound wave. Frequency = speed/wavelength
✔✔what an object is made of affects: - ✔✔the speed of the sound wave
✔✔the length of the object affects: - ✔✔the wavelength of the sound wave
