History of slit drums:

A slit drum is a hollow percussion instrument, usually carved or constructed from bamboo or wood into a box with one or more slits in the top. Various varieties are found around the world. This Bamboo Drum can be held in one hand and light weight making it very easy to transport. 

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 mallet. The resonating chamber increases the volume of the sound produced by the tongue and presents the sound through an open port. 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.