F₀Timing and Tone Contrasts in Luganda

Abstract

Scholars of Luganda (Bantu, Uganda) have described a contrast between falling and high tone, which is limited to syllables with a long vowel or a coda. The contrast has been represented with H on the first mora of a falling-tone syllable and on both moras in a high-tone syllable. This article explores this contrast through an instrumental study of the timing of f₀ events in Luganda. It was found that the 2-tone classes differed in the timing of both the f₀ rise and the subsequent f₀ fall, supporting a reanalysis of the contrast as one between an early high tone and a late high tone. It was also found that for the speakers in this study, the contrast was limited to syllables with long vowels. The timing of f₀ events was sensitive to the duration of segments in the CVC interval centered on the high-toned syllable, including non-moraic elements and consonants outside the syllable. The association of a tone to a syllable identifies the segments relevant for the timing of the f₀ contour, but that timing is not directly sensitive to the interval of the syllable.

Phonetic implementation of high-tone spans in Luganda

“…In Table 6, presenting the analysis of peak delay, there are significant main effects for segmental interval duration C 1 and V 1 , indicating that the f 0 rise is timed with respect to the segments of the span-initial syllable, as found previously by Myers et al (2018). When those segments are longer, peak delay is correspondingly longer.…”

“…In this paper, we will assume for purposes of discussion that the tone-bearing unit in Luganda is the syllable, contrary to previous work that has identified the mora as the tone-bearing unit in the language (Tucker, 1962;Hyman, 1992;Hyman & Katamba, 1993;Hyman & Katamba, 2010). Myers et al (2018) found that the timing of the f 0 peak and the subsequent fall depended on the duration of the onset, the vowel of the syllable, as well as the duration of the postvocalic consonantal interval. They did not find that this dependency was sensitive to whether or not the segment was moraic, and so concluded that the mora was not relevant to the timing of f 0 events in Luganda.…”

“…In (1), high tone is associated with a single syllable, which is a short high-tone span. Such a span in Luganda has an f 0 rise that begins before the onset of the high-toned syllable and ends in an f 0 maximum around the end of the vowel, followed immediately by an f 0 fall over the course of the next syllable (Myers, Namyalo, & Kiriggwajjo, 2018). The timing of the f 0 rise offset depends on the duration of the onset, vowel, and coda of the high-toned syllable, with longer segments associated with a later rise offset (Myers et al, 2018).…”

“…Such a span in Luganda has an f 0 rise that begins before the onset of the high-toned syllable and ends in an f 0 maximum around the end of the vowel, followed immediately by an f 0 fall over the course of the next syllable (Myers, Namyalo, & Kiriggwajjo, 2018). The timing of the f 0 rise offset depends on the duration of the onset, vowel, and coda of the high-toned syllable, with longer segments associated with a later rise offset (Myers et al, 2018). The f 0 rise and fall is coordinated quite precisely with the segments, as in other languages (Silverman & Pierrehumbert, 1990;Prieto, van Santen, & Hirschberg, 1995;Arvaniti, Ladd, & Mennen, 1998;Xu, 1998;Myers, 2003).…”

The intonation of yes–no questions in Luganda

“…There is a contrast between high and low tone in both long and short syllables, but the contrast between falling and high tone only occurs in long syllables. Both high and falling tone are characterized by a rise in f0 followed immediately by a fall, but they differ in that the f0 peak occurs earlier in the syllable in falling tone than in high tone (Myers, Namyalo & Kiriggwajjo 2019).…”