# Acoustic Correlates of Uvularization in Mawo Qiang: Toward a More Comprehensive Phonetic Account of the Plain-Uvularized Vowel Contrast

Amélie Elmerich, Angelique Amelot, Katia Chirkova, Yao Dong, John H Esling, Claire Pillot-Loiseau, Lise Crevier-Buchman

<figure><img src="image_1.png" /></figure>

## To cite this version:

Amélie Elmerich, Angelique Amelot, Katia Chirkova, Yao Dong, John H Esling, et al.. Acoustic Correlates of Uvularization in Mawo Qiang: Toward a More Comprehensive Phonetic Account of the Plain-Uvularized Vowel Contrast. Phonetic Approaches to Under-Documented Languages (With a Special Emphasis on Tibeto-Burman Languages), Sep 2025, Aubervillers, France. hal-05361425

HAL Id: hal-05361425

https://hal.science/hal-05361425v1

Submitted on 12 Nov 2025

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

<figure><img src="image_2.png" /></figure>
# Acoustic Correlates of Uvularization in Mawo Qiang: Toward a More Comprehensive Phonetic Account of the Plain-Uvularized Vowel Contrast

A recent finding in the study of Tibeto-Burman languages in Sichuan, China, is the presence of paired vowel sets, where one vowel is plain and the other exhibits secondary articulatory features such as velarization, uvularization, or pharyngealization. This rare phenomenon provides valuable insights into phonological typology and lower vocal tract phonetics. However, despite its theoretical importance, the contrast remains underexplored due to limited data and a lack of instrumental studies. Among the documented cases, the Mawo variety of Qiang, which contrasts plain and uvularized vowels, offers the clearest example, based on experimental research with two male speakers (Evans et al. 2016). This study builds on that work by examining a larger speaker sample and incorporating additional acoustic parameters to further clarify the vowel contrast.

## Data and methodology

The dataset comprises 1,051 vowel tokens from simultaneous audio and electroglottographic (EGG) recordings of 24 minimal pairs contrasting plain and uvularized vowels ( /i ~ iʰ/, /ə ~ əʰ/, /u ~ uʰ/, /a ~ aʰ/), produced as isolated CV sequences with alveolar onsets (/t d s n l/) by four male and five female Mawo speakers. The data were manually segmented and annotated in Praat with EGG boundaries marked by the initial and final oscillations.

## Acoustic measures

The analysis integrates formant-based measures (F1 to F4), fundamental frequency (F0), and voice quality metrics, specifically the open quotient (OQ), to examine the acoustic and phonatory properties of the vowel sets. Formant values were extracted from the acoustic signal, while both F0 and OQ were derived from the EGG signal, which provides more stable F0 tracking. OQ was calculated from the derivative of the EGG waveform (dEGG) using Praatdet (Kirby 2017), after high-pass filtering at 75 Hz to remove low-frequency noise and enhance glottal pulse detection. Peaks that can be interpreted as the glottal opening and closing phases were identified in the dEGG signal using Howard's (1995) method, with a 3/7 amplitude threshold. Formants were extracted at the vowel midpoint (in Hz), while F0 and OQ were measured throughout the entire vowel duration, which was divided into ten equal intervals (0–10%, ..., 90–100%) using custom MATLAB scripts.

## Results

The corpus reveals substantial inter-speaker variation in the realization of plain versus uvularized vowels, particularly in vowel quality, phonation, and pitch. Averaging across speakers often obscures these contrasts, underscoring the need for speaker-specific analysis. To capture this variation, we examined three dimensions systematically.

In the formant analysis, we tested whether the contrast reflects uvularization as a secondary articulation, defined as dorsum raising and backing toward the uvula. Two methods were applied: (1) articulatory modeling of F1 and F2 (Maeda 1982) to simulate tongue positions, and (2) analysis of the F4-F3 distance as an acoustic correlate of uvular constriction (Fant 1960/1970). Modeling of /i, ə, u, a/ and their uvularized counterparts revealed speaker-specific strategies, with little evidence for uvularization except in /u/, where retraction is better explained by fronting of plain /u/, phonetically [u]. Overall, F2 lowering emerged as the primary acoustic cue, with minimal contribution from other formants.

The second method showed consistent narrowing of F4-F3 for uvularized vowels in most speakers, with gender effects. For example, female speakers' mean F4-F3 distance was 593 Hz for /uʰ/ versus 1060 Hz for /u/, while male speakers showed narrower differences (1000
Hz vs. 1200 Hz). However, exceptions occur, particularly with /iʰ/, where some speakers showed no narrowing.

Finally, analysis of OQ and F0 indicated that two-thirds of speakers, regardless of gender, used distinct phonation types across the contrastive vowel sets, ranging from statistically significant differences to strong tendencies. These phonatory patterns were also correlated with pitch differences. Figure 1 shows the pattern in OQ and F0 values: OQ ≈ 0.5 indicates modal phonation, < 0.5 suggests “tense” voice, and > 0.5 indicates lax voice. The “tense” quality is most likely the result of laryngeal constriction.

<figure><img src="image_3.png" /><figcaption>Figure 1. OQ (left) and F0 (right) values for three male and three female Mawo speakers, with plain vowels in blue and uvularized vowels in orange.</figcaption></figure>

The consistent relationship observed between phonation type and pitch—higher pitch associated with tenser phonation and lower pitch with breathier phonation—indicates a potential difference in OQ as a distinguishing characteristic between the two vowel sets across these speakers. This difference may be linked to variations in laryngeal height.

## Discussion

Our findings refine Evans et al.’s (2016) definition and characterization of the contrastive vowel sets in Mawo. The contrast is not restricted to vowel quality but is multidimensional, involving several covarying cues—vowel quality, phonation, and pitch—together with coarticulatory effects on the preceding consonant (McKeever 2025). On this basis, we propose that the contrast is more appropriately analyzed at the syllable level rather than as a purely segmental vowel contrast, as previously suggested. Speakers display some flexibility in the cues they prioritize, provided that the overall contrast is preserved.

Given the multidimensional nature of the contrast and the considerable inter-speaker variation it entails, further research is needed—particularly on potential adjustments in larynx height. Such work should ideally draw on a larger speaker sample, more extensive corpora, and complementary articulatory evidence, for example from ultrasound imaging.

## References

Fant, G. 1960/1970. *Acoustic Theory of Speech Production With Calculations based on X-Ray Studies of Russian Articulations*. The Hague & Paris: Mouton.

Evans, J., J. T.-S. Sun, C. Chiu, & M. Liou. 2016. Uvular approximation as an articulatory vowel feature. *Journal of the International Phonetic Association* 46.1: 1–31.

Kirby, J. 2017 Praatdet: Praat-based tools for EGG analysis (v0.1.1). https://doi.org/10.5281/zenodo.1117189.

Maeda, S. 1982. A digital simulation method of the vocal-tract system. *Speech Communication*, 1. 3-4: 199-229.
McKeever, L. 2025. Use of Locus Equations to Quantify Anticipatory Coarticulation of Uvularized Vowel Contrasts in the Mawo Variety of Northern Qiang. Presentation at Phon-UDL, September 18, 2025.