• the balaphone, which is similar to a xylophone and is made up of wooden bars, 
• the djembe which is a drum shaped like a goblet and played with the hands 
• the talking drum that is played with a hooked stick and can be used to imitate speech by creating different pitches and slides.

A Background look on Yiri

In Yiri, there six musicians each dedicated to a different instrument:

• Madou Kone - vocals, balaphone and flute.
• Sydou Traore - vocals and balaphone.
• Jacouba Kone - djembe
• Francois Naba - vocals, tam-tam, dundun and maracas.
• Keresse Sanou - talking drum
• Tidiane Hema who does vocals and plays the maracas.

There are three clear strands in Yiri:

• The balaphone ostinato - in combination, these produce a complex polyphonic texture.
• The drum ostinato - in this piece they play a relentless one-bar pattern.
• The vocal line - this is a simple pentatonic call and response structure.

Points to note about Yiri by Koko:

• The tempo stays unvaried.
• The beat is regular and unvarying providing a good beat.
• The drum ostinatos persist throughout the music.
• The dynamics are largely unvaried. 
• Yiri is in the key of G flat major and is hexatonic meaning it is based on a size-note scale.
• The balaphones tend to play short patterns from high to low emphasising G and D. They have solo breaks in between choruses which are more vituosic.
• It is in 4/4 which is four crochet beats to every bar. However it does revert to other metres in a few bars such as 6/4 and 3/4.
• Syncopation is used mostly in the vocals and balaphone sections.
• The drums play a rhythmic ostinato which lasts throughout the piece consisting of a quaver and two semi-quavers played over and over again.
• There is monophonic texture at the beginning which leads on to be heterophonic.
• Balaphone at beginning uses tremolos and grace notes as decoration.