Speech Surrogates

Slit-log drum system used by the Jabo people of Liberia, described by Herzog (1945). The instrument itself is a very large (over 8 feet tall) membrane drum with a single head, struck with two heavy wooden beaters. Two pitches are distinguishable, based on striking at the center or near the edge. The language is tonal. Herzog analyzes Jabo to have four tonal registers with a number of both contrastive and derived contours, grammatical tone processes, and vowel concatenation/shortening. Dwyer (1981) attributes a different, three-tone analysis to Lukau (1975): “Since the publication of Herzog’s (1945) article, Lukau (1975) has reanalyzed the tonal system of the Jabo dialect of Grebo and has found it to have three tone levels rather than four as proposed by Herzog” (Dwyer (1981:442).The surrogate system is based on abridgement; the drum’s two pitches correspond to a reduction of the language’s tonal phonology. Pitch-tone mapping is necessarily less exact than the related Jabo slit-log drum, given the few number of contrastive pitch levels; Herzog also suggests that this may also be an effect of the physical cumbersomeness of the mallets (228). The overall system is comparable to that of the slit-log drum, with tone (including grammatical tone) and some syllable structure encoded. However, breathy-voiced and complex onsets are apparently always encoded with a flam, unlike the variable encoding on the slit-log drum. Content is restricted to a small number of rote signals for long-distance communication and one lexical ideogram, a “series of evenly spaced rapid beats, to call for quiet and attention” that is repeated three times before a signal is struck (222). A smaller version of the drum plays a “purely musical, simple rhythmic role” alongside the slit-log drum in dance settings (223).

Slit-Log Drum

Summary

Bibliography