Thoughts on the Typology of Central African Music:
Melody in Central African music is determined by the tones of the language. As I mentioned in a previous blog Steve Reich uses this approach in his work Different Trains. Also the melodic line can be transposed allowing a wider range of intervals. Often the lines descend in the form of terraced movement resting on “successve levels”. (Arom, 19)
Tempo is the only constant. The speed of a piece of music never varies. Only melody, rhythm and instrumental patterns may change in a musical discourse.
There are different techniques of plurivocality or multi-part singing: Heterophony, overlapping and homophony. André Gide relates his impressions of a ‘tam-tam’ in 1928, “but imagine this tune yelled by a hundred persons not one of whom sings the exact note. It is like trying to make out the main line from a host of little strokes. The effect is prodigious and gives an impression of polyphony and of harmonic richness.”
Simha Arom aptly describes the features of this heterophony which I will delineate in a list:
- A melody whose outline is refracted by a kind of halo
- The voices are slightly unfocused
- Minute variants
- A coming and going of dissonances
- Overlapping between solo and chorus parts (Gide called this ‘brocading’)
- Often in the middle of this process a singer will sustain a single note thus creating an intermittent drone. (Arom, 21)
Homophony on the other hand is the most common form of multi-part singing. This form of plurivocality involves parallel movement of the voices. Typically they are in intervals of 4ths, 5ths and octaves. Often certain tribes are known for singing distinctly with these intervals as 8-5-4 tribes and some sing in 3rds. (Arom, 22)
In Pentateuch (1983) a grand divisi orchestra, choir and soprano work written when I was 23 (with influences from Ligeti and Xenakis) the three male choir groups sing for an extended period in 5ths. Each group takes its turn singing a phrase in 5ths while the soprano voice predominates above in a quasi call and response. My intent was to create a very raw, basic and forceful sound in the midst of a constellation of divisi polyphonic and polyrhythmic wind, brass, percussion and string sections.
Tags: André Gide, brass, Central African music, Different Trains, Heterophony, homophony, Ligeti, micro polyphony, orchestra, percussion, polyphonic, polyrhythmic, Simha Arom, Steve Reich, tam tam, tempo, Xenakis