SOUNDS OF SCIENCE
PHYSICS IS PHUN – March 2007
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Please be seated
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Welcome and Thanks (Dan)
Web Pages of Interest
Title Page
Comment: Analysis of why sounds sound the way they do.
Reference Book
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1. STANDING WAVES AND THE OVERTONE SERIES
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The Overtone Series
Overtone series with Fourier synthesizer
TRANSVERSE WAVES
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Standing waves on a string
G3-28: SUSPENDED SLINKY
The Overtone Series
H4-31: VIOLIN
LONGITUDINAL WAVES
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Standing waves in air columns
G3-28: SUSPENDED SLINKY
The Overtone Series
H3-14: TWIRL-A-TUNE
Comment: In real instrument many harmonics combine to produce complex wave.
STANDARD ELECTRONIC WAVES
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Standard electronic wave forms
H1-13: WAVEFORM GENERATOR, SPEAKER AND OSCILLOSCOPE.
(a) sine wave
(b) sawtooth
(c) pulse train
(d) triangular wave
(e) square wave
(page 2)
2. FOURIER SYNTHESIS
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Fourier’s Theorem
Comment on Fourier’s theorem (amplitude and phase)
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H4-01: FOURIER SYNTHESIS
(a) sine wave
(b) sawtooth wave
(c) pulse train (optional?)
(d) triangular wave (optional)
(e) square wave
Comments: Harmonics create wave shape and sound
Change amplitude (hear) and phase (do not hear)
Generalize to any wave
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Slides of synthesis of triangular wave, sawtooth wave, pulse train, square wave
3. FOURIER OR SPECTRUM ANALYSIS
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Fourier analysis or Spectrum analysis
ELECTRONIC WAVES
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H4-02: FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM
(a) sine wave
(b) sawtooth
(c) pulse train
(d) triangular wave
(e) square wave
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Fourier Spectra
(a) sine wave
(b) sawtooth
(c) pulse train
(d) triangular wave
(e) square wave
(page 3)
MUSICAL SOUNDS
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Analysis of Musical Sounds
Recorder background
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H4-02: FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM
(a) recorder
(b) violin
(c) crumhorn
(d) clarinet
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Fourier Spectra
(a) recorder
(b) violin
(c) crumhorn
(d) clarinet
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Factors in Tone Quality
H1-52: AUDIOTAPE 82 MIN - SCIENCE OF SOUND - LONG VERSION (Overtones)
Comments: transients (piano, tuned percussion)
inharmonicities (tuned percussion, piano)
vibrato
chorus effect
4. FORMANTS
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Singing Formant
Origin of vocal formants
Simplified formant model
Vocal formant examples
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H4-02: FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM
Vocal Sounds
(a) ooo
(b) ahh
(c) eee
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Formant Regions for Vowel Sounds
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H4-02: FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM
Vocal Sounds
(a) vowel sequence: boot-all-balm-but-bat-met-bit-beet
(b) eee at various frequencies
(page 4)
5. AUDIO SPECTROGRAPHS
Comment: Time dependence of audio spectrum
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AUDIO SPECTROGRAMS
VOCAL FORMANTS FOR VOWEL SOUNDS
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H4-02: FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM
Vocal "WOW"
H6-06: SYNTHESIZER - WOW
Synthesizer and voice "WOW"
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Voice spectrograms of four words
Comment on use of formants to teach speech to profoundly deaf persons
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H6-04: HELIUM VOICE
Dangers of breathing helium
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He and SF6 Voice
H6-05: SULFUR HEXAFLUORIDE VOICE
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Thanks to Colleague for helping with program.
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Goodbye
Pre-Show Demonstrations
H4-02: FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM (Oscilloscope)
H5-01: EAR MODEL
RESONANCE TUBE WITH PLUNGER
H4-11: SAVART'S DISKS
H4-53: MOOG ROGUE SYNTHESIZER
H4-55: YAMAHA DX7S DIGITAL SYNTHESIZER
G3-28: SUSPENDED SLINKY
H3-05 KUNDT'S TUBE - OSCILLATOR DRIVEN
H3-13 ROARING TUBE - 8 FT
H3-17 FLAME TUBE
WAVETEK ON AUDIO CART (Guess the frequency.)
SOUND LEVEL METER (Guess the decibel level.)
CLICK ILLUSION CART (in hallway)