Paper long abstract:

Transmission systems of the verbal message by means of drum or slit gong sounds have been widely elaborated in Sub-Saharan African societies, where the tone languages are spoken, except for the languages classified as West-Atlantic languages. Among so called “talking drums”, the bifacial hourglass type drums, beaten by a hooked wooden stick, of which the player regulates the tension of faces by grasping the strings which link the two faces, like Yoruba iya-ilu, in order to produce different tones, are widely used among West African peoples. Talking drums of this type are suitable to send verbal messages with different tones which are freely combined to express different meanings. Otherwise, to send the verbal messages with two distinctive tones, a pair of large and small drums, like Ashanti atumpan, is appropriate.