Vowel formant frequencies are predictable from the location of vocal tract constrictions

Evidence

A commonly referenced set of average formant frequency values for men, women and children for a number of vowels, taken from Peterson and Barney (1952), is shown in Table 4.3. Formant frequency values for these vowels can be predicted with reference to their articulation. For example, the vowel in beat has a constriction toward the front of the tongue in the region of both N2 and N3 (see Figure 4.38), and reference to Figure 4.39 suggests that F1 is lowered in frequency, and F2 and F3 are raised from the values one would expect for the neutral vowel. The vowel in part, on the other hand, has a significant constriction in the region of both A2 and A3 (see Figure 4.38), resulting in a raising of F1 and a lowering of both F2 and F3 from their neutral vowel values. The vowel in boot has a constriction at the lips, which are also rounded so as to extend the length of the vocal tract, and thus all formant frequencies are lowered from their neutral vowel values. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1349

Categorization

Category: Causal Relationships

• DEFINE: Clarifies how vowel articulation maps onto measurable formant frequencies.
• XREF: Connects to acoustic-phonetics literature (Peterson and Barney 1952) and the neutral vowel concept used in speech science.

Related

• Tongue and lip constriction locations systematically shift formant frequencies from neutral values (similarity 0.92)
• Vowels are distinguished by formant frequencies controlled by tongue, jaw, and lips (similarity 0.88)
• Formants are standing-wave resonances of the vocal tract itself (similarity 0.84)
• Vowel identification depends on formant peaks being representable in the output spectrum. (similarity 0.84)
• Vowels are distinguished by the location of F1 and F2 formants (similarity 0.83)
• Vowels are distinguished by the two lowest vocal tract resonance frequencies. (similarity 0.83)
• Vowel identity depends on the locations of the two lowest vocal tract formants (similarity 0.83)
• Lip constriction lowers the frequencies of all vocal tract formants (similarity 0.81)
• All vowel distinctions reduce to tongue position, openness, and lip rounding (similarity 0.81)
• The vocal tract behaves acoustically like a stopped tube of constant diameter (similarity 0.81)
• Vowels keep the vocal tract open and vary little by context, unlike consonants (similarity 0.80)
• Pitch-fluctuation contrast coding may outperform formant-peak rate coding for vowels (similarity 0.80)
• Vocal tract resonance multiplies each vocal fold harmonic to shape the sung vowel spectrum (similarity 0.80)
• Identifying a vowel requires at least two of its formants (similarity 0.79)
• Tongue and lip constrictions shift vocal resonances mostly near their nodes, not antinodes. (similarity 0.79)