YOP Sound Lecture.ppt 2551KB Jun 23 2011 10:24:32 AM
Please
be
Seated
The physics of sound:
What makes musical
tones different?
Special Lecture for the 2005 Year of Physics
in coordination with the
French National Center for Scientific Research
and the
French Embassy in Washington DC
Special Guests:
Michẻla Castellengo, Research Director,
Musical Acoustics Lab, University of Paris
Hugues Genevoire, Research Engineer,
Musical Acoustics Lab, University of Paris
Charles Besnainous, Research Engineer,
Musical Acoustics Lab, University of Paris
Joseph Curtin, stringed instrument maker
Benoît Rolland, bow maker
Serge de Laubier, musician-researcher
The Overtone Series
Standing waves in a string
The Overtone Series
Standing waves in air columns
The Overtone Series
Standard electronic wave forms
•
•
•
•
•
Sine wave
Sawtooth wave
Pulse train
Triangular wave
Square wave
Fourier’s Theorem:
Any complex wave can be
“synthesized” by adding its
harmonics together with the
proper amplitudes and phases.
“Fourier synthesis” and “Fourier analysis”
Fourier Synthesis
Fourier Synthesis
Sawtooth wave
Fourier Synthesis
Pulse train wave
Fourier Synthesis
Triangular wave
Fourier Synthesis
Square wave
Fourier Analysis
or
Spectrum Analysis
Sine Wave Spectrum
Sawtooth Wave Spectrum
Pulse Train Spectrum
Triangular Wave Spectrum
Square Wave Spectrum
Analysis
of
Musical Sounds
Recorder Wave and Spectrum
Violin Wave and Spectrum
Crumhorn Wave and Spectrum
Clarinet Wave and Spectrum
Factors in Tone Quality
1. Amplitudes of harmonics
2. Attack and decay transients
3. Inharmonicities
4. Formants
5. Vibrato
6. Chorus effect
Vocal Formants
Origin of Vocal Formants
(~17.5 cm closed tube)
Mode:
Frequency: Vocal range:
f1 = 500 Hz
150-850 Hz
f3 = 1500 Hz
500-2500 Hz
f5 = 2500 Hz
1500-3500 Hz
Simple formant model
From Thomas D. Rossing, The Science of Sound, second edition
Vowel formant production
Source: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
Vowel Formant Frequencies
From Donald E. Hall, Musical Acoustics, Second Edition
The
Singers
Formant
Averaged spectral energy distribution:
Light: ordinary speech
Dark: orchestral accompaniment
Brown: Good singer with orchestra
Johan Sundberg: The Acoustics of the Singing Voice; Sci. Amer., March 1977
Sound
Spectrograms
Vocal Formant spectra
“OO”
“AH”
“EE”
Vocal Spectrogram of Formants
Voice and Synthesizer “wow”
Matching vocal spectrograms
Kay Elemetrics, Computerized Speech Laboratory
Helium Voice
Singing frequency remains the same
(vibration of vocal folds)
Formant frequencies rise because
She >> Sair
Why?
Vowel formant production
Source: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
Speed of Sound
in
Helium and Sulfur Hexafluoride
He
SF6
M/Mair
1/7
4.6
Vs/S
2.6
0.5
The End
Thank you for your attention
We are on the web at
http://www.physics.umd.edu/lecdem/
Animated Gifs compliments of bellsnwhistles.com
be
Seated
The physics of sound:
What makes musical
tones different?
Special Lecture for the 2005 Year of Physics
in coordination with the
French National Center for Scientific Research
and the
French Embassy in Washington DC
Special Guests:
Michẻla Castellengo, Research Director,
Musical Acoustics Lab, University of Paris
Hugues Genevoire, Research Engineer,
Musical Acoustics Lab, University of Paris
Charles Besnainous, Research Engineer,
Musical Acoustics Lab, University of Paris
Joseph Curtin, stringed instrument maker
Benoît Rolland, bow maker
Serge de Laubier, musician-researcher
The Overtone Series
Standing waves in a string
The Overtone Series
Standing waves in air columns
The Overtone Series
Standard electronic wave forms
•
•
•
•
•
Sine wave
Sawtooth wave
Pulse train
Triangular wave
Square wave
Fourier’s Theorem:
Any complex wave can be
“synthesized” by adding its
harmonics together with the
proper amplitudes and phases.
“Fourier synthesis” and “Fourier analysis”
Fourier Synthesis
Fourier Synthesis
Sawtooth wave
Fourier Synthesis
Pulse train wave
Fourier Synthesis
Triangular wave
Fourier Synthesis
Square wave
Fourier Analysis
or
Spectrum Analysis
Sine Wave Spectrum
Sawtooth Wave Spectrum
Pulse Train Spectrum
Triangular Wave Spectrum
Square Wave Spectrum
Analysis
of
Musical Sounds
Recorder Wave and Spectrum
Violin Wave and Spectrum
Crumhorn Wave and Spectrum
Clarinet Wave and Spectrum
Factors in Tone Quality
1. Amplitudes of harmonics
2. Attack and decay transients
3. Inharmonicities
4. Formants
5. Vibrato
6. Chorus effect
Vocal Formants
Origin of Vocal Formants
(~17.5 cm closed tube)
Mode:
Frequency: Vocal range:
f1 = 500 Hz
150-850 Hz
f3 = 1500 Hz
500-2500 Hz
f5 = 2500 Hz
1500-3500 Hz
Simple formant model
From Thomas D. Rossing, The Science of Sound, second edition
Vowel formant production
Source: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
Vowel Formant Frequencies
From Donald E. Hall, Musical Acoustics, Second Edition
The
Singers
Formant
Averaged spectral energy distribution:
Light: ordinary speech
Dark: orchestral accompaniment
Brown: Good singer with orchestra
Johan Sundberg: The Acoustics of the Singing Voice; Sci. Amer., March 1977
Sound
Spectrograms
Vocal Formant spectra
“OO”
“AH”
“EE”
Vocal Spectrogram of Formants
Voice and Synthesizer “wow”
Matching vocal spectrograms
Kay Elemetrics, Computerized Speech Laboratory
Helium Voice
Singing frequency remains the same
(vibration of vocal folds)
Formant frequencies rise because
She >> Sair
Why?
Vowel formant production
Source: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
Speed of Sound
in
Helium and Sulfur Hexafluoride
He
SF6
M/Mair
1/7
4.6
Vs/S
2.6
0.5
The End
Thank you for your attention
We are on the web at
http://www.physics.umd.edu/lecdem/
Animated Gifs compliments of bellsnwhistles.com