Assimilation

According to Simo Bobda (2000b: 188), a following rounded vowel and possibly also a rounded consonant favor /ɔ/  rather than /Λ/. However, this is dubious for two reasons: first, Simo Bobda's examples of assimilation to a following rounded vowel, suppose and conduct, do not really illustrate the phenomenon since in RP the nucleus of the initial syllables of these words is /ə/, not /Λ/. These words do not therefore meet the input requirements for the /Λ > ɔ/ substitution process. Second, Simo Bobda's argument that following “rounded consonants” (/b/ is described as +ROUNDED) tend to trigger /ɔ/ is doubtful, since roundedness is not an intrinsic, distinctive feature of English consonants but is determined by the phonetic context. Possibly, roundedness is confused with labial place of articulation, but even in that case the proposed assimilation rule does not work: cf. drug (Speaker B) and result (A), which both have /ɔ/ without the following consonant being labial or intrinsically rounded. But note the different vowels in the otherwise phonologically quite similar drug /ɔ/ and blood /a/ (Speaker B; both voiced throughout, both plosive+ liquid+ vowel+ plosive), which demonstrates that /a/ and /ɔ/ are used in very similar contexts, in this case before /g/ and /d/, whose roundedness is subphonemic and depends on the preceding vowel and not vice versa.