Slit drum

In Africa, such drums are situated in strategic locations for optimal acoustic transmission (e.g., along a river or valley), in order to be used for long-distance communication.

[1] The ends of a slit drum are closed so that the shell becomes the resonating chamber for the sound vibrations created when the tongues are struck, usually with a stick or mallet.

If the resonating chamber is the correct size for the pitch being produced by the tongue, which means it has the correct volume of airspace to complete one full sound wave for that particular pitch, the instrument will be more efficient and louder.

[2] In the central islands, slit drums are erected vertically, and adorned with carvings on the outer surface, representing spirits.

While traditional on one island only, this adorned type of drums have become one of the national emblems of Vanuatu as a whole.