English alveolar obstruents /t d s/ are wildly unstable in that their surface forms are rarely [t d s]. This paper focuses on the respective palatoalveolar set of surface forms [tʃ dʒ ʃ]. While many speakers produce these allophones in onsets before /ɹ/ (1) (Smith, et al., 2019), a smaller set of North American speakers, most notably near New York City and Montréal, also produce them before [w] (2) (Nelson & Flynn, 2021).
1) a. betray /bitɹeɪ/ → [bɪ.ˈtʃɹeɪ]
- drone /dɹoʊn/ → [dʒɹoʊn]
- sri* /ʃri/ → [ʃri] (*/sr/ is not permitted in English)
2) a. between /bitwin/ → [bɪ.ˈtʃwin]
- Dwayne /dweɪn/ → [dʒweɪn]
- swing /swiŋ/ → [ʃwiŋ]
This paper analyzes this phonological process as a case of reanalysis of enhancement cues and phonological features (Keyser & Stevens, 2006). In typical English pronunciation, lip rounding enhances [-anterior] consonants including /tʃ dʒ ʃ/. I therefore claim that these speakers have reinterpreted the phonetic rounding cue spread by rhotic and labio-velar approximants as indicating the phonological feature [-anterior] in preceding obstruents.
Thus, when these speakers produce a sequence of [+anterior] /t d s/ before rounded approximants /w ɹ/, they apply a phonological change (Bach & Harms, 1972) of [+anterior] to [-anterior], so that the rounding enhancement cue matches the surface representation. In English, this additionally forces the features [+strident] and [+distributed], as all English posterior obstruents carry these features, resulting in surface allophones [tʃ dʒ ʃ].