Phonetic Realization of Automatic (Downdrift) and Non-automatic Downstep in Akan

This paper deals with the question whether automatic and non-automatic downstep are distinct processes or can be regarded as the same phenomenon. Downstep is seen as a lowering of the pitch register, relatively to which tones are scaled. The distinction between the two types of downstep arises from differences in their tonal surface structure: In the case of automatic downstep a L(ow) tone intervening H(igh) tones triggers downstep (HLH); in the case of non-automatic downstep the L tone trigger is not realized phonetically (H!H, ! indicates downstep). Our controlled experimental data on downstep in Akan suggest that the degree of lowering is the same in both cases contrary to what has been claimed earlier in the literature.