Vocal Tract Measurement
The vocal tract is like the internet: a series of tubes. For central vowels, we can model the vocal tract as a simple tube, like a cylinder that starts at the vocal tract and ends at the lips.
\( \begin{aligned} F_n &= \frac{(2n - 1)c}{4l} \end{aligned} \)
where
\( \begin{aligned} c &= \text{speed of sound (m/s)} \\ l &= \text{length of simple tube (m)} \\
In a vocal tract, the speed of sound is about 350 m/s. So...
\( \begin{aligned} l &= \frac{350(2n - 1)}{4F_n} \\ \end{aligned} \)
Estimate height from vocal tract length:
\( \begin{aligned} H &= 7l + 0.55 \, \text{(m)} \\ \end{aligned} \)
Activity: Guess Who
Match the speaker with the spectrogram (A-G), using vocal tract length estimation and given height. You can download the audio here.
Sara Audio file: ______ |
Trang Audio file: ______ |
Wesley Audio file: ______ |
Ellen Audio file: ______ |
Leanne Audio file: ______ |
Juvenile 1 Audio file: ______ |
Juvenile 2 Audio file: ______ |
You Audio file: ______ |
Some good references: