articulator: the 8-tube tongue root region, the 9-tube tongue body region corresponding to a quarter wavelength at the second formant frequency, the 6-tube blade region corresponding to a quarter wavelength at the third formant frequency, and the 4-tube lip

In the first paper of this report “Toward phonetically grounded distinctive features. Part I: Acoustic-articulatory correlations in a four-region model of the vocal tract”, the formant frequencies F1–F4 and the quality (or gain) factors Q1–Q4 are correlated with the positions, areas, or area ratios formed by the four active articulators: tongue root, tongue body, blade, lips. Among the findings, it was determined that: 1) when the blade position (location of smallest constriction) moves toward the lips, F3 frequency shifts higher; 2) blade aperture (blade area normalized by lip area) is directly correlated with Q3. The present paper applies these two blade relations to actual coronal speech sounds. To this end, an auditorily-based estimator of Q3 is developed: the peak energy factor PE3. The asymptotic ERB (equivalent rectangular bandwidth) of the auditory filter is about one-sixth octave wide. Hence one-sixth octave is adopted as the unit of formant frequency resolution. Measured F3 frequencies are observed to span six one-sixth octaves (one octave). The six F3 distinctions are classified by the primary and secondary features of blade position [anterior posterior] and [AB RB], where AB and RB are advanced blade and retracted blade. Dentalveolars are [+anterior –posterior]; postalveolars are [–anterior +posterior]. Blade aperture is captured by the feature pair [elevated depressed]. Laminals are [+elevated –depressed]; apicals are [–elevated –depressed]. When the blade aperture increases from a small value (laminal) through a medium value (apical) to a large value (depressed), PE3 also increases. The coronal fricatives of American English, Toda, and Ubykh are examined as well as the coronal stops, nasals, and liquids of Central Arrernte. Both the palatographic evidence and the PE3 measures consistently show the laminality of [s] and the apicality of [ʃ ʂ]. Furthermore, the [s ʃ] sounds are always [+anterior]. In American English, for example, there is no statistically significant difference in F3 frequency between laminal [s] and apical [ʃ], which indicates very similar blade positions.