slit-log drum, àgìdìgbè

Slit-log drum system employed by the Idoma people of Nigeria, described by Armstrong (1953). The instrument itself (ágogo) is a slit-log drum with varying thickness from one side of the slit to the other, producing a high (“male”) and a low (“female”) pitch (871). Armstrong analyzes the language as having H, M, and L register tones. In the surrogate system, H and L tones are encoded as high and low pitches. It is not evident how M tones, the “least common”, are encoded; they may be variably assimilated to either H or L in order to preserve the direction of tonal transitions (for example, MH encoded as LH to preserve the rising transition) (872). Additionally, “it is said that mid tones may be produced … by striking both lips simultaneously”, but no direct evidence was available (871). Armstrong also reports a pair of differently pitched drums, which could theoretically produce  four distinct pitches, employed in the four-toned Agala variety of Idoma (871). Content for large larger slit-log drums (àgìdìgbè) includes announcements of deaths or war, and lineage names. Smaller drums are employed for “practice or amusement on the farm” (871). The large drum is also used non-linguistically to accompany ritual dances (872).

Blench, R. (1987). Idoma musical instruments. African Music: Journal of the International Library of African Music, 6(4), 42–52. https://doi.org/10.21504/amj.v6i4.1260,Armstrong, R. G. (1953). 46. TALKING INSTRUMENTS IN WEST AFRICA. In T. A. Sebeok & J. Umiker-Sebeok (Eds.), Speech Surrogates: Drum and Whistle Systems. 1976. (pp. 865–878). De Gruyter Mouton. https://doi.org/10.1515/9783110804423-017