1. Physics 1251 The Science and Technology of Musical Sound Unit 3 Session 31 MWF The Fundamentals of the Human Voice Unit 3 Session 31 MWF The Fundamentals of the Human Voice

2. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice What is the frequency of a palm pipe at 20 C that is 500 mm long and has an internal diameter of 35 mm? What are the first three audible harmonics? A palm pipe is a stopped cylinder. Therefore f 1 = v/4L′; L′ = 0.500 m+ 0.3 (0.035 m) = 0.5105 f 1 = 343/4(0.511) =85.75/0.511 =168 Hz. [E 3 +33¢] f 3 = 3f 1 = 3 (168) = 504 Hz. [B 4 + 35 ¢] f 5 = 5f 1 = 5 (168) = 840 Hz. [G 5 ♯ + 19 ¢]

3. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice 1′ Lecture: The vocal folds, located in the larynx, produce vibrations in the vocal tract. The vocal folds, located in the larynx, produce vibrations in the vocal tract. The vocal tract is a stopped air column approximately 17 cm long. It resonates at a fundamental frequency of about 500 Hz. The vocal tract is a stopped air column approximately 17 cm long. It resonates at a fundamental frequency of about 500 Hz. The shape of the vocal tract provides an acoustic filter of the harmonics produced by the vocal folds. The shape of the vocal tract provides an acoustic filter of the harmonics produced by the vocal folds.

4. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Anatomy of the Human Voice 80/20 The vocal tract is the instrument of the human voice. Vocal Tract: Lungs—source of air Lungs—source of air Lungs Trachea—wind pipe Trachea—wind pipe Larynx—voice box Larynx—voice box Pharynx—mouth and nose Pharynx—mouth and nose Larynx Trachea Pharynx

5. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Anatomy of the Human Voice 80/20 The sound of the human voice originates in the larynx. Larynx Larynx

6. Open Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Anatomy of the Human Voice 80/20 The larynx (or voice box) contains the vocal folds. Larynx Closed Vocal Folds

7. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Anatomy of the Human Voice 80/20 The vocal folds rapidly open and close, introducing pulsations of air into the vocal tract. Vocal Folds Lower Vocal Tract

8. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Anatomy of the Human Voice 80/20 The vocal folds rapidly open and close, introducing pulsations of air into the vocal tract. Vocal Folds Lower Vocal Tract

9. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Video of Laryngoscopy

10. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice The Vocal Folds--Function 80/20 The vocal folds are controlled by muscle and actuated by air moving between them, closing due to the Bernoulli Effect, opening by tension. Vocal Folds Phonation Air Flow When flow is interrupted folds open.

11. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice The Vocal Folds 80/20 The pressure waveform produced by the action of the vocal folds is an asymmetrical sawtooth, rich in harmonics. 80/20 The fundamental frequency of the voice is determined by the properties of the vocal folds, not the vocal tract. Vocal Folds snap open are pulled shut by air flow

12. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Resonances of Vocal Tract f 1 = v/4L = 353/(4 ‧ 0.17) = 519 Hz f 3 = 3f 1, f 5 = 5f 1 … L≈ 17 cm 80/20 The Vocal Tract is a “lossy” stopped pipe ~17 cm long with a fundamental frequency of ~500 Hz. v =343 + 0.6(37-20) =353 m/s ~500 Hz ~1500 Hz ~2500 Hz

13. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Formants of Vocal Tract f 1 = v/4L = 353/(4 ‧ 0.17) = 519 Hz f 3 = 3f 1, f 5 = 5f 1 … L≈ 17 cm 80/20 The Vocal Tract filters the spectrum generated by the vocal folds; the frequency filter is called the Formant. Amplitude Frequency Formant

14. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Speech 80/20 The individual units of speech are called phonemes. 80/20 The individual units of speech are called phonemes. The classes of (English) phonemes are: The classes of (English) phonemes are: Unvoiced Plosives‒ p, t, soft k (c, q, x)Unvoiced Plosives‒ p, t, soft k (c, q, x) Voiced Plosives‒ b, d, gVoiced Plosives‒ b, d, g Fricatives‒ f, v, thFricatives‒ f, v, th Sibilants‒ s (c), z, sh, zh, jSibilants‒ s (c), z, sh, zh, j Liquids‒ l, rLiquids‒ l, r Nasals‒ m, n, ngNasals‒ m, n, ng Semi-vowels‒ w, ySemi-vowels‒ w, y Vowels‒ a, e, i, o, uVowels‒ a, e, i, o, u

15. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Spectrogram of Human Speech

16. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice 80/20 The shape of the Vocal Tract determines the frequency of the Formants. “ah” “eh” “oh” “ oo”

17. Physics 1251Unit 3 Session 31 The Fundamentals of the Human Voice Summary: The vocal folds, located in the larynx, produce vibrations in the vocal tract. The vocal folds, located in the larynx, produce vibrations in the vocal tract. The vocal tract is a stopped air column approximately 17 cm long, that resonates at ~500, 1500 and 2500 Hz. The vocal tract is a stopped air column approximately 17 cm long, that resonates at ~500, 1500 and 2500 Hz. The shape of the vocal tract provides an acoustic filter, called the formant, that modifies the amplitude of the harmonics produced by the vocal folds. The shape of the vocal tract provides an acoustic filter, called the formant, that modifies the amplitude of the harmonics produced by the vocal folds.