Automatic and Nonautomatic Downstep in Chumburung: An Instrumental Comparison
Keith Snider, Canada Institute of Linguistics and SIL
Few phonological phenomena have so captured the attention of theorists and continued to
baffle them as the phenomenon of tonal downstep. Downstep is the lowering of the tonal
register that sometimes occurs between adjacent, otherwise identical tones. It is cumulative,
and successive occurrences of the phenomenon result in ever lower settings of the tonal
register. Automatic downstep refers to downstep when the Low tone that causes the downstep
is nonfloating, and nonautomatic downstep refers to downstep when the Low tone is floating.
An issue of interest to phonologists is whether the degree of downstep which is attributable to
automatic downstep is the same as that which is attributable to nonautomatic downstep. Since
both phenomena involve Low tones, and both result in downward shifts in register, most
theories of downstep formally equate, in one way or another, the two types of downstep. If
both phenomena lower the tonal register to the same degree phonetically, those theories that
formally equate the two are justified. Instrumental support for or against formally equating
the two is, however, greatly lacking. In view of this, the present work reports on an
intstrumental comparison of automatic and nonautomatic downstep in Chumburung, a Kwa
language spoken in Ghana and concludes that the two types of downstep are phonetically
indistinguishable.