THE PHONOLOGICAL REALITY OF LOCUS EQUATIONS ACROSS MANNER CLASS DISTINCTIONS - PRELIMINARY-OBSERVATIONS

The present study extends the phonological realm of locus equations to include nasals, fricatives, approximants and unaspirated voiceless st ops. The question of interest was to determine if locus equation slope s and y-intercepts could serve as phonetic descriptors for place of ar ticulation across varied manner classes. Fourteen speakers, 7 male and 7 female, produced CVC tokens with 10 medial vowels and initial conso nants varying across manner classes. F-2 onset and F-2 vowel frequenci es were acoustically determined and plotted as locus equations. Fairly distinct clustering of slope and y-intercept coordinates were found f or labial, dental/alveolar and velar places of articulation. Approxima nts (/w, j, r, V) formed a unique cluster of points characterized by s lope = 0 and contrasted solely by y-intercepts - correlates of steady- state onset frequencies of approximant productions. The consistent lin earity observed in all locus equation plots across all consonant-vowel tokens is discussed according to the orderly-output constraint that h ypothesizes that the robust linearity of the acoustic FZ transition on set-to-offset relationship exists to best serve neural encoding and pe rception of the speech signal.