COMD 5070 Utah State University -COMD
5070 exam 1 verified /passed
4 features of the scientific method
1) Science is empirical- we collect data and interpret it (based on data)
2) Science is Deterministic - Things are not random. Because of cause and effect, we can draw
generalizations from the data that we have and extrapolate
3) Science is predictive - if you do this, then that will happen.
4) Science is parsimonious - use the simplest explanation possible, try to describe things in economical
terms so we can understand it. Use the simplest terms possible, but no simpler.
Why do SLPs use technology
1) Overcome listener bias - computer isn't influenced by what it has heard before. It is a consistent,
reliable measure.
2) Describe severity objectively - standardizes measures of speech
3) Track progress over time - helps demonstrate treatment efficacy
4) Helps to comply with ASHA's focus on EBP - provides hard data to measure rather than just gut
feelings about progress based on experience.
5) Biofeedback- computer display in real time - ex: visipitch shows intonations on screen in real time,
shows them progress as they speak, better than playing back a recording.
How can acoustics help?
acoustics can tell us a lot about what is going on that can't be seen. Acoustics is a way of using
quantitative measures to to describe a physical phenomenon, rather than relying on our human
impressions
Frequency
how frequently a waveform repeats. Measured in Hz (cycles per second). Within the same window
length, a higher frequency sound wave will show more repetitions than a lower frequency sound
wave
simplest sound
pure tone (sine wave)
Pitch
the subjective measure of frequency; you cannot measure pitch with an instrument. You can have
people match pitch perception to frequencies.
Intensity
amplitude or size of a sound.Adjusting volume, is adjusting the physical intensity of sound.
Why use a logarithmic scale for intensity?
This is necessary because the highest amplitude sound we can perceive is 1 trillion times the softest
sound we can perceive (120 dB).
Loudness
Perceptual characteristic of sound. Listener can judge loudness, there is no equipment that can
measure loudness. Human reaction to the amplitude of a sound. Can be measured with a psycho-
physical scale.
, Greatest sensitivity to loudness is between
1,000 - 5,000 Hz, threshold is much higher at very low or very high frequencies
Why do audiometers use HL and not SPL?
to compensate for known differences in human hearing sensitivity.
Equal loudness contours
Created by presenting a known frequency (1,000 Hz) and then other tones are played and the listener
has to adjust the loudness until it sounds the same as the 1,000 Hz tone
In order to perceive low amplitude sounds at low frequency as the same loudness as higher frequency
sounds....
have to be adjusted up a lot for them to be perceived as the same loudness as the original sound
at high intensity,
the sounds seem to be equal in loudness to intensity.
general rule is that a 6-10 dB increase
is generally perceived as double as loud
Frequency Difference limen
smallest change in frequency that is detectable by a listener. As frequency increases, the DL becomes
much greater
Intensity Difference limen
as intensity decreases, Dls become larger
How does duration influence perception of loudness?
The longer the sound, the more audible it becomes. The more sound energy ( intensity or frequency,
the more audible it becomes) Kind of like baking a cake; increase the temp, decrease the time to a
certain point.
When a fundamental is deleted:
the brain compensates because in a harmonic series, the frequencies are separated at even intervals
and your brain can fill in the missing portion. There is a qualitative difference but most people
perceive the notes as being the same as with the fundamental frequency by filling in the missing
fundamental.
how many semitones in one octave
12. each semitone is a non-linear step in terms of # of Hz from one semitone to the next. However,
they all sound equal to us.
Octave
5070 exam 1 verified /passed
4 features of the scientific method
1) Science is empirical- we collect data and interpret it (based on data)
2) Science is Deterministic - Things are not random. Because of cause and effect, we can draw
generalizations from the data that we have and extrapolate
3) Science is predictive - if you do this, then that will happen.
4) Science is parsimonious - use the simplest explanation possible, try to describe things in economical
terms so we can understand it. Use the simplest terms possible, but no simpler.
Why do SLPs use technology
1) Overcome listener bias - computer isn't influenced by what it has heard before. It is a consistent,
reliable measure.
2) Describe severity objectively - standardizes measures of speech
3) Track progress over time - helps demonstrate treatment efficacy
4) Helps to comply with ASHA's focus on EBP - provides hard data to measure rather than just gut
feelings about progress based on experience.
5) Biofeedback- computer display in real time - ex: visipitch shows intonations on screen in real time,
shows them progress as they speak, better than playing back a recording.
How can acoustics help?
acoustics can tell us a lot about what is going on that can't be seen. Acoustics is a way of using
quantitative measures to to describe a physical phenomenon, rather than relying on our human
impressions
Frequency
how frequently a waveform repeats. Measured in Hz (cycles per second). Within the same window
length, a higher frequency sound wave will show more repetitions than a lower frequency sound
wave
simplest sound
pure tone (sine wave)
Pitch
the subjective measure of frequency; you cannot measure pitch with an instrument. You can have
people match pitch perception to frequencies.
Intensity
amplitude or size of a sound.Adjusting volume, is adjusting the physical intensity of sound.
Why use a logarithmic scale for intensity?
This is necessary because the highest amplitude sound we can perceive is 1 trillion times the softest
sound we can perceive (120 dB).
Loudness
Perceptual characteristic of sound. Listener can judge loudness, there is no equipment that can
measure loudness. Human reaction to the amplitude of a sound. Can be measured with a psycho-
physical scale.
, Greatest sensitivity to loudness is between
1,000 - 5,000 Hz, threshold is much higher at very low or very high frequencies
Why do audiometers use HL and not SPL?
to compensate for known differences in human hearing sensitivity.
Equal loudness contours
Created by presenting a known frequency (1,000 Hz) and then other tones are played and the listener
has to adjust the loudness until it sounds the same as the 1,000 Hz tone
In order to perceive low amplitude sounds at low frequency as the same loudness as higher frequency
sounds....
have to be adjusted up a lot for them to be perceived as the same loudness as the original sound
at high intensity,
the sounds seem to be equal in loudness to intensity.
general rule is that a 6-10 dB increase
is generally perceived as double as loud
Frequency Difference limen
smallest change in frequency that is detectable by a listener. As frequency increases, the DL becomes
much greater
Intensity Difference limen
as intensity decreases, Dls become larger
How does duration influence perception of loudness?
The longer the sound, the more audible it becomes. The more sound energy ( intensity or frequency,
the more audible it becomes) Kind of like baking a cake; increase the temp, decrease the time to a
certain point.
When a fundamental is deleted:
the brain compensates because in a harmonic series, the frequencies are separated at even intervals
and your brain can fill in the missing portion. There is a qualitative difference but most people
perceive the notes as being the same as with the fundamental frequency by filling in the missing
fundamental.
how many semitones in one octave
12. each semitone is a non-linear step in terms of # of Hz from one semitone to the next. However,
they all sound equal to us.
Octave
