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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:
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The physics of sound:What makes musicaltones 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
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”
Factors in Tone Quality 1. Amplitudes of harmonics 2. Attack and decay transients 3. Inharmonicities 4. Formants 5. Vibrato 6. Chorus effect
Frequency: f1 = 500 Hz f3 = 1500 Hz f5 = 2500 Hz Vocal range: 150-850 Hz 500-2500 Hz 1500-3500 Hz Origin of Vocal Formants(~17.5 cm closed tube) Mode:
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
TheSingersFormant 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
Vocal Formant spectra “OO” “AH” “EE”
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
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