A kora is a harp built from a large calabash cut in half and covered with cow skin to make a resonator with a long hardwood neck. The skin is supported by two handles that run under it, and it supports a notched double free-standing bridge. It doesn’t fit into any one category of musical instruments, but rather several, and must be classified as a “double-bridge-harp-lute.” The strings run in two divided ranks, making it a double harp. They do not end in a soundboard but are held in notches on a bridge, making it a bridge harp. They originate from a string arm or neck and cross a bridge directly supported by a resonating chamber, making it a lute too.
The sound of a kora resembles that of a harp, though when played in the traditional style, it bears a closer resemblance to flamenco and delta blues guitar techniques. The player uses only the thumb and index finger of both hands to pluck the strings in polyrhythmic patterns (using the remaining fingers to secure the instrument by holding the hand posts on either side of the strings). Ostinato riffs (“Kumbengo”) and improvised solo runs (“Birimintingo”) are played at the same time by skilled players.
Kora players have traditionally come from griot families (also from the Mandinka nationalities) who are traditional historians, genealogists and storytellers who pass their skills on to their descendants. The instrument is played in Guinea, Guinea-Bissau, Mali, Senegal, Burkina Faso and the Gambia. A traditional kora player is called a Jali, similar to a ‘bard’ or oral historian. Most West African musicians prefer the term ‘jali’ to ‘griot’, which is the French word.
Traditional koras feature 21 strings, eleven played by the left hand and ten by the right. Modern koras made in the Casamance region of southern Senegal sometimes feature additional bass strings, adding up to four strings to the traditional 21. Strings were traditionally made from thin strips of hide, for example antelope skin – now most strings are made from harp strings or nylon fishing line, sometimes plaited together to create thicker strings.
By moving leather tuning rings up and down the neck, a kora player can retune the instrument into one of four seven-note scales. These scales are close in tuning to western major, minor and Lydian modes.
In the late 20th century, a 25-string model of the kora was developed, though it has been adopted by only a few players, primarily in the region of Casamance, in southern Senegal. Some kora players such as Seckou Keita have double necked koras, allowing them to switch from one tuning to another within seconds, giving them increased flexibility.
The kora music being part of the oral tradition, its music was not written until the 20th century. The ethnomusicologists were the only ones to note some traditional airs in the normal grand staff method using the G clef and the F clef.
Nowadays, kora scores are written on a single G clef, following the Keur Moussa notation system. This notation system was created for the kora in the late 1970s by Brother Dominique Catta, a monk of the Keur Moussa Monastery (Senegal). The seven low notes that should be written on the F clef are replaced by Arabic or Roman numerals and written on the G clef.
While griots still compose in the traditional way (without writing scores), some Western musicians began to write partitures for the kora and adopted the Keur Moussa notation system at the beginning of the 1980s.