An investigation of variation in the production of glottalized consonants

In the study of the consonants of the world’s languages, consonants with glottal airstream mechanisms are less well studied than their pulmonic counterparts despite being geographically widespread [I. Maddieson, In: Dryer, M. S. and Haspelmath, M. (eds.) WALS Online (v2020.4)]. In particular, there is very little large-scale research about the acoustic variability in their production in connected speech. In the present study, we investigate the acoustic variability present in the realization of ejectives and implosives from the online corpus of Georgian and kiSwahili [Ardila, R. et al., Proc. 12th Conf. on Lang. Res. and Eval. (LREC 2020), 4211–4215, 2020]. The Common Voice corpora contain recordings of speakers reading sentences. For the present study, we hand corrected automatically force-aligned recordings of the pulmonic (for comparison) and glottalized stop consonants in each language. We then use the aligned recordings to investigate the variability in a variety of acoustic measures (e.g., closure duration and rise time) that can be easily extracted from the segmental boundaries. We discuss the variability in the acoustic realization of the consonants and describe the articulatory aspects related to these productions.