Department of Linguistics, The University of Hong Kong, Hong Kong.
J Acoust Soc Am. 2024 Apr 1;155(4):2285-2301. doi: 10.1121/10.0025461.
Fronting of the vowels /u, ʊ, o/ is observed throughout most North American English varieties, but has been analyzed mainly in terms of acoustics rather than articulation. Because an increase in F2, the acoustic correlate of vowel fronting, can be the result of any gesture that shortens the front cavity of the vocal tract, acoustic data alone do not reveal the combination of tongue fronting and/or lip unrounding that speakers use to produce fronted vowels. It is furthermore unresolved to what extent the articulation of fronted back vowels varies according to consonantal context and how the tongue and lips contribute to the F2 trajectory throughout the vowel. This paper presents articulatory and acoustic data on fronted back vowels from two varieties of American English: coastal Southern California and South Carolina. Through analysis of dynamic acoustic, ultrasound, and lip video data, it is shown that speakers of both varieties produce fronted /u, ʊ, o/ with rounded lips, and that high F2 observed for these vowels is associated with a front-central tongue position rather than unrounded lips. Examination of time-varying formant trajectories and articulatory configurations shows that the degree of vowel-internal F2 change is predominantly determined by coarticulatory influence of the coda.
在大多数北美英语变体中，都观察到了元音 /u, ʊ, o/ 的前化现象，但主要是从声学而非发音的角度进行分析。由于 F2（元音前化的声学相关物）的增加可能是任何缩短声道前腔的动作的结果，因此仅靠声学数据并不能揭示说话人用来产生前化元音的舌位前化和/或唇不圆化的组合。此外，前化后元音的发音在多大程度上根据辅音环境而变化，以及舌和唇在整个元音过程中如何影响 F2 轨迹，这些问题仍未解决。本文介绍了来自两种美国英语变体（南加州沿海地区和南卡罗来纳州）的后元音前化的发音和声学数据。通过对动态声学、超声和唇视频数据的分析，表明两种变体的说话人在发前化 /u, ʊ, o/时都会使用圆唇，并且这些元音的高 F2 值与中央前舌位有关，而不是不圆唇。对时变共振峰轨迹和发音配置的检查表明，元音内部 F2 变化的程度主要取决于尾音的协同发音影响。
