By Edgardo Civallero | Sara Plaza
Today, the term "saya" denotes two different Andean rhythms. The original Afro-Bolivian saya is performed by the Afro-descendants communities settled in the yungas of Bolivia, and its characteristics are similar to other Afro-American rhythms such as those from Peru and Venezuela. It consists in a combination of melodic lines being played by percussion instruments in a 4/4 meter: one of the drums or cajas de la saya stresses the main beats while the other instruments and voices interweave syncopated lines.
For its part, the "Andean" saya does not have any relation with the former. The most widespread version, the one popularized by Los Kjarkas, is a variant of another rhythm, the huayno, but adapted to a 6/8 meter. The bombo stresses the first two beats of each subdivision leaving the third silent, producing a very characteristic sound.
There is another version of the "Andean" saya, much more similar to the huayno than the one already mentioned, performed in a 2/4 meter; the subdivisions of the first beat are strongly stressed by the bombo, while the subdivisions of the second beat are unstressed.
Both variants of the "Andean" saya are played with the same instruments and have the same arrangement as those used for the huayno. In recent times, this type of saya has come to be known as "saya caporal" or simply "caporal", in order to avoid being confused with (or misused/taken advantage by) the Bolivian Afro-descendants original rhythm.
Afro-Bolivian Saya, in Wikipedia.