Figure 2.

(a) Experimental γ(f) measured while phonating the neutral vowel /ə/ (in the target word “herd”), magnitude (above), and phase (below). Blue line shows the raw measurement, while the red line shows the smoothed with Savitsky–Golay algorithm [14] and interpolated spectra (having removed harmonics of the voice), revealing vocal tract resonances as “notches” (magnitude spectrum) and “dips” (phase spectrum), indicated by yellow vertical bands; (b) corresponding analytical γ(f) spectra modeled for an ideal baffled open-closed cylinder with a length of 170 mm; the “notches” and “dips” correspond closely in frequency and general structure with the experimental spectra in (a).