Describe how you would identify the following from a spectrogram (be sure to identify the type of spectrographic display you would need to examine). Evidence of an unstable supra-laryngeal vocal tract during a sustained phonation task Evidence of unstable vocal fold vibration during sustained vowel production Evidence of inter-harmonic energy during sustained vowel production.
Added by Daniel F.
Step 1
A wideband spectrogram provides better temporal resolution, which is essential for observing rapid changes in the vocal tract and vocal fold vibrations. Show more…
Show all steps
Your feedback will help us improve your experience
Dominador Tan and 73 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
The sound of the talking or singing voice is produced by the vocal cords together with the vocal tract. When air is expelled through your throat, the vocal cords vibrate. For an adult man, this vibration has a fundamental frequency of about $110 \mathrm{Hz}$, with harmonics at $220 \mathrm{Hz}, 330 \mathrm{Hz}, 440 \mathrm{Hz}, \ldots .$ Sound with components at all these frequencies then passes through the vocal tract (Fig. $\mathrm{P} 13.67 \mathrm{A}$ ), which can be modeled as two pipes, one representing the larynx and another representing the oral cavity. When making the sound "ah" as in the word father, the larynx acts approximately as a pipe closed at both ends (with just small openings at the vocal cords and the entry to the oral cavity), while the oral cavity acts as a pipe that is open at one end (at the lips). The resonant frequencies of these two "pipes" then affects which of the harmonics of the vocal cords are strongest in the final sound. Figure $\mathrm{P} 13.67 \mathrm{B}$ shows the spectrum of the vowel sound "ah"; the strongest harmonics are near $750 \mathrm{Hz}, 1100 \mathrm{Hz}$, and $2500 \mathrm{Hz}$. These peaks in the spectrum are called formants. If the larynx has a length of $16 \mathrm{cm}$ and the oral cavity a length of 11 cm, which harmonic of which section of the vocal tract gives rise to each of these formants?
Sound
Applications
In the larynx, sound is produced by the vibration of the vocal cords. The diagram in Figure 12.44 is a cross section of the vocal tract at one instant in time. Air flows upward (in the $+z$ direction) through the vocal tract, causing a transverse wave to propagate vertically upward along the surface of the vocal cords. In a typical adult male, the thickness of the vocal cords in the direction of airflow is $d=2.0 \mathrm{~mm} .$ High-speed photography shows that for a frequency of vibration of $f=125 \mathrm{~Hz}$, the wave along the surface of the vocal cords travels upward at a speed of $v=375 \mathrm{~cm} / \mathrm{s}$. Take $t$ to be time, $z$ to be displacement in the $+z$ direction, and $\lambda$ to be wavelength. Which of the following is a possible mathematical description of the wave in Problem $72 ?$ A. $A \sin [2 \pi f(t+z / v)]$ B. $A \sin [2 \pi f(t-z / v)]$ C. $A \sin (2 \pi f t) \cos (2 \pi z / \lambda)$ D. $A \sin (2 \pi f t) \sin (2 \pi z / \lambda)$
Audible Sound. Provided the amplitude is sufficiently great, the human ear can respond to longitudinal waves over a range of frequencies from about 20.0 $\mathrm{Hz}$ to about 20.0 $\mathrm{kHz}$ . (a) If you were to mark the beginning of each complete wave pattern with a red dot for the long-wavelength sound and a blue dot for the short-wavelength sound, how far apart would the red dots be, and how far apart would the blue dots be? (b) In reality would adjacent dots in each set be far enough apart for you to easily measure their separation with a meter stick? (c) Suppose you repeated part (a) in water, where sound travels at 1480 $\mathrm{m} / \mathrm{s}$ . How far apart would the dots be in each set? Could you readily measure their separation with a meter stick?
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD