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# Sound Audiology .

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Sound Audiology. Perry C. Hanavan, Au.D. Audiologist. Sound. Vibration Perception. Propagation of Sound. Condensations ____________ Example of molecular motion Components of sinusoid Transverse wave simulation Applet: Square, triangle, simulation. Components of Sound.
Transcripts
Slide 1

﻿Sound Audiology Perry C. Hanavan, Au.D. Audiologist

Slide 2

Sound Vibration Perception

Slide 3

Propagation of Sound Condensations ____________ Example of atomic movement Components of sinusoid Transverse wave reproduction Applet: Square, triangle, reenactment

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Components of Sound Physical Psychological - - - Intensity Loudness Frequency ________ Duration Length

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Intensity Decibel Unit of measure of power dB = 10logR (R=ratio)

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Problem Human listening to force dynamic range is very expansive 1 Softest sound 1,000,000,000,000 Loudest sound

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Intensity Dynamic Range 1 10 100 1000 10000 100000 1000000 10000000 100000000 1000000000 10000000000 100000000000 1000000000000 10000000000000 100000000000000

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Honey I Shrunk the Kids 1,3,5 or 1, 4, 8, 12 and so on diminishes dynamic range to some degree 1, 10, 100, 1000 psychologists more Yet, element range is very extensive

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Solution Ratio Compare power esteem (number) to reference 8:4 (truly 2:1)

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Aha! Proportion Compare 2 Numbers 1/1 =1 10/1 =10 100/1 =100 1000/1 =1000 10000/1 100000/1 1000000/1 10000000/1 100000000/1 1000000000/1 10000000000/1 100000000000/1 1000000000000/1 10000000000000/1 100000000000000/1

Slide 11

Logarithms!! Since a proportion has been changed over Next stride: Convert proportions to logs (base 10)

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Lets Work with Logs!!! 1 = 0 10 = 1 100 = 2 100000000000000 = ? 14 .1 = - 1 .01 = - 2 .00000000001 = ? - 11

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So is that a decibel? So far we have 1. Changed over a proportion to a number (10:1=10) 2. Changed over the proportion to a log (10=1) We have made a ____ (A.G. Ringer) There are 10 decibels in a bel 2 bels = 20 decibels 8 bels = 80 decibels

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WOW!!! Decibel = 10 log _____ A decibel comprises of: 1. Proportion 2. Log 3. X10

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That was simple, how about we hone: Integer: 10 X 10 = 100 Log: 1 + 1 = 2 Integer: 1000 X 1000 = ? Log: 3 + 3 = 6 Now take the log times 10 to change over to decibels

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Not terrible, how about we attempt this: Integer: 100/10 = 10 Log: 2 - 1 = 1 Integer: 1000000/100 = ? Log: 6 – 2 = 4 Now take the log times 10 to change over to decibels

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Ok, I can do that, yet… Some numbers are very simple to work with in logs However, a few numbers you have to utilize an adding machine or look in a CRC book of tables Or you can retain a few numbers and figure heaps of logs Hint: log = bel

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Oh, one additionally thing: Measures of ________ are regularly made in Sound Pressure Level (SPL) as opposed to Intensity Level (IL) IL: measure of vitality streaming through a 1cm 2 surface region SPL: measure of weight applied on a 1cm 2 surface region IL = SPL 2 dB IL =10logR parallels dB SPL =20logR

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dB Intensity Level Measure of vitality Reference 1.0 X 10 - 16 watts/cm 2 or .0000000000000001 watts/cm 2

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dB Sound Pressure Level Measure of drive or weight Reference 20 microPA

Slide 21

Sound Pressure Level 20/20 = 1:1 40/20 = 2:1 60/20 = 3:1 200/20 = 10:1 Intensity Level 1.0x10 - 16/1.0x10 - 16 2.0x10 - 16/1.0x10 - 16 3.0x10 - 16/1.0x10 - 16 4.0x10 - 16/1.0x10 - 16 1.0x10 - 15/1.0x10 - 16 Ratios in IL and SPL

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dB IL =10logR or dB SPL =20logR Ratio No. Log dB IL dB SPL 1:1 1 0 0 0 2:1 2 .3010 3.0 6.0 3:1 3 .4771 4.8 9.6 4:1 4 .6020 6.0 12.0 5:1 5 .6990 7.0 14.0 6:1 6 .7781 7.8 15.6 7:1 7 .8451 8.5 17.0 8:1 8 .9030 9.0 18.0 9:1 9 .9542 9.5 19.0 10:1 10 1.000 10.0 20.0

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Can you do this? Twofold SPL? Twofold IL? Triple SPL Triple IL? Fourfold SPL? Fourfold IL?

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