SPTH1002 Lecture Notes - Lecture 5: Density Of Air, Low Frequency, Formant
26 Oct 2018
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Define sound in a parent friendly manner
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Sound is movement changes in the air density of particles.
Sound comes from one's mouth to another's ear via air
particles being knocked on, back and forth in some ways. The
change in air pressure changes into sound
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What is Sound?
Be familiar with visual representation of sound
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Waveforms is a way of representing the amount of sound
pressure as time goes pass
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Waveform Examples
What information can we gather from images of speech
waveforms?
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Speech Sounds
"Top-down processes affect our hearing"
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Let's test a theory
How are these different?
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When we hear things, we process the sound and then
overlay it with everything else have going on such as our
expectation, settings (what we prior know about the
child/setting)
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A child may be trying to say a voiceless but it may come out
as a voiced sound, they may think they are saying a voiceless
in their mine but we just can't perceive it
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Provide examples that highlight this difference
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Loudness is a perceived thing
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Covert contrast - speech contrast that is present in child's
speech but not perceptible by ear or by us (listeners)
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Hearing vs Perceiving
What are the main dimensions of sound
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Describing Sound
What computers measures and is seen on graphs
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The changes in air pressure transcribed onto a graph by time
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Amplitude
What makes loudness different from amplitude?
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Subjective thing we perceive
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Loudness
Low frequency means things repeat less often than high
frequency
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The number of times the pressure waves repeat per second
(Hz)
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Frequencies
Discuss the normal human hearing frequency range
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Changes as people gets older
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What frequencies can you hear?
Basic Acoustics and Analysis for Speech Pathologists
Thursday, 10 November, 2016
3:32 PM
SPTH1002 Page 12.1
Document Summary
Sound is movement changes in the air density of particles. Sound comes from one"s mouth to another"s ear via air particles being knocked on, back and forth in some ways. The change in air pressure changes into sound. Waveforms is a way of representing the amount of sound pressure as time goes pass. When we hear things, we process the sound and then overlay it with everything else have going on such as our expectation, settings (what we prior know about the child/setting) A child may be trying to say a voiceless but it may come out as a voiced sound, they may think they are saying a voiceless in their mine but we just can"t perceive it. Covert contrast - speech contrast that is present in child"s speech but not perceptible by ear or by us (listeners) What computers measures and is seen on graphs. The changes in air pressure transcribed onto a graph by time.
