1. WELCOME to Physics is Phun

2. Please be Seated

3. Physics Lecture-Demonstration Web Site Summer Programs for Youth Physics Olympics Physics Question of the Week

4. The Sounds of Science Physics is Phun March 2007

5. Reference book: The Physics of Sound, 3 rd edition (2005) by Richard E. Berg and David G. Stork published by Pearson/Prentice-Hall

6. The Overtone Series

7. Standing waves in a string

8. The Overtone Series

9. Standing waves in air columns

10. The Overtone Series

11. Standard electronic wave forms Sine wave Sawtooth wave Pulse train Triangular wave Square wave

12. Fourier’s Theorem: Jean Baptiste Joseph Fourier (1768 - 1830) Any physical function that varies periodically with time with a frequency f can be expressed as a superposition of sinusoidal components of frequencies: f, 2f, 3f, 4f,... --from “Wikipedia”

13. Fourier Synthesis Sawtooth wave

14. Fourier Synthesis Pulse train wave

15. Fourier Synthesis Triangular wave

16. Fourier Synthesis Square wave

17. Fourier Analysis or Spectrum Analysis

18. Sine Wave Spectrum

19. Sawtooth Wave Spectrum

20. Pulse Train Spectrum

21. Triangular Wave Spectrum

22. Square Wave Spectrum

23. Analysis of Musical Sounds

26. Fourier Analysis of Sounds of Musical Instruments

27. Recorder Wave and Spectrum

28. Violin Wave and Spectrum

29. Crumhorn Wave and Spectrum

30. Clarinet Wave and Spectrum

31. Factors in Tone Quality 1. Amplitudes of harmonics 2. Attack and decay transients 3. Inharmonicities 4. Formants 5. Vibrato 6. Chorus effect

32. The Singing Formant

33. Origin of Vocal Formants (~17.5 cm closed tube) Frequency: f 1 = 500 Hz f 3 = 1500 Hz Vocal range: 150-850 Hz 500-2500 Hz Mode:

34. Simple formant model

35. Origin of Vocal Formants (~17.5 cm closed tube) Frequency: f 1 = 500 Hz f 3 = 1500 Hz Vocal range: 150-850 Hz 500-2500 Hz Mode:

36. Vowel formant production Source: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

37. Vowel Formant Frequencies

38. Sound Spectrograms

39. Vocal formants for vowel sounds

40. Voice and Synthesizer “Wow”

41. Vocal Spectrograms

42. Computerized Speech Laboratory Courtesy of Kay Elemetrics Corp.

43. Helium Voice Singing frequency remains the same (vibration of vocal folds) Formant frequencies rise because S he >> S air Why?

44. Vowel formant production Source: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

46. Speed of Sound in Helium and Sulfur Hexafluoride HeSF 6 M/M air 1/74.6 V s /S2.60.5

48. The End See you next time! We are on the web at http://www.physics.umd.edu/lecdem/ Animated Gifs compliments of bellsnwhistles.com