Cross-dialectal variation in formant dynamics of American English vowels

Abstract

This study aims to characterize the nature of the dynamic spectral change in vowels in three distinct regional varieties of American English spoken in the Western North Carolina, in Central Ohio, and in Southern Wisconsin. The vowels /(, , e, ae, a(/ were produced by 48 women for a total of 1920 utterances and were contained in words of the structure /bVts/ and /bVdz/ in sentences which elicited nonemphatic and emphatic vowels. Measurements made at the vowel target ͑i.e., the central 60% of the vowel͒ produced a set of acoustic parameters which included position and movement in the F1 by F2 space, vowel duration, amount of spectral change ͓measured as vector length ͑VL͒ and trajectory length ͑TL͔͒, and spectral rate of change. Results revealed expected variation in formant dynamics as a function of phonetic factors ͑vowel emphasis and consonantal context͒. However, for each vowel and for each measure employed, dialect was a strong source of variation in vowel-inherent spectral change. In general, the dialect-specific nature and amount of spectral change can be characterized quite effectively by position and movement in the F1 by F2 space, vowel duration, TL ͑but not VL which underestimates formant movement͒, and spectral rate of change.

A cross-dialectal acoustic study of the monophthongs and diphthongs of Welsh

“…Trajectory length constitutes a measure of spectral change that tracks formant movement in the F1∼F2 space across equidistant sections. In the present study, as in Fox & Jacewicz (2009), this involved four sections: 20%-35%, 35%-50%, 50%-65% and 65%-80%. The TL of each section was calculated on the basis of the following formula, where VSL n constitutes the length of one vowel section:…”

“…Note that TL has been shown to constitute a more accurate measure of spectral change than VECTOR LENGTH, which involves calculating the Euclidean distance from the diphthong onset point to its offset point (Fox & Jacewicz 2009). However, TL is a time-normalized measure and, as a result, does not indicate how quickly, or slowly, spectral change occurs in real time.…”

“…In addition to formant frequency measurements, the TRAJECTORY LENGTH (TL) and SPECTRAL RATE OF CHANGE (SpecROC) were determined for each diphthong, following Fox & Jacewicz's (2009) account. Trajectory length constitutes a measure of spectral change that tracks formant movement in the F1∼F2 space across equidistant sections.…”

“…As a measure of spectral change, trajectory length (TL) was computed, following Fox & Jacewicz's (2009) account. Recall (from Section 3.3 above) that this involved calculating the Euclidean distance in the F1∼F2 space for each of the four sections of the diphthongs.…”

Forming New Vowel Categories in Second Language Speech: The Case of Polish Learners' Production of English /I/ and /e/

“…We could not use a standard /hVd/ context (Peterson and Barney 1952) because while English uses a glottal fricative /h/, Polish has a velar /x/ (Jassem 2003). This would have made vowels from both languages incomparable due to the fact that consonantal effects may persist throughout the whole vowel portion, including its target (Fox and Jacewicz 2009). The target /bVt/ words were embedded in carrier sentences I say /bVt/ this time in English and Mówię /bVt/ tym razem in Polish in a non-utterance final position.…”