ngoni

The Ngoni is a tetracorde (4) tunable Lute from Guinea West-Africa.
it can also be built with only three strings.
The instrument is known to be very old, possibly older than the Balafon and the Kora and is played all over West Africa under many different names, depending on the ethnic group and language of the people playing it; from the costal region, to the north (Kerona for Peul). It is one of the most symbolic instrument for Jelis.
Initially covered with snake skin, It is now composed of a wooden pole with a goatskin covered wooden resonance chamber in a canoe shape. In some versions, the resonance chamber is made out of calabash instead of wood.
Nylon strings are individually  attached  to  the  pole by means of leather rings.
Though nylon strings are used nowadays, it used to be animal hairs (horsehair at some point). The strings  are  tuned by moving  the self-blocking rings  up  and  down the pole.
A resonator is sometimes attached at the end of the wooden pole.
The tuning of the instrument is directly related to the piece of traditional music being played, so there are many possible tuning for this instrument. A single string version of this instrument is called "Molaru" (Peul).