Semi Rhythmic Drumming, also known as polyrhythmic drumming, was originally found in African "Fire Circles," traditional African gatherings around a fire with drumming, dancing and chanting. In this tradition, the community comes together around the fire for the purpose of individual and communal transformation, using rhythm as the vehicle.
Fire Circle aficionados embrace the polyrhythmic complexity and ensemble orientation of the African music, and even if all the drummers are not traditionally trained, the rhythm music at a Fire Circle is eclectic and symphonic, deeply rooted in rhythmic traditions and solid playing, listening, and improvisation skills.
At the African Fire Circles, polyrhythmic drumming is achieved by the existence of a critical mass of drummers who know how to play together and how to create the framework that provides the reliable polyrhythmic pulse.
In the late 1960's, polyrhythmic drumming was adopted by some traditionally trained drummers and transformed into a technique where a single drummer is able to create the same kind of framework and provide a stable and reliable semi-rhythmic pulse, which eliminated the need for multiple drummers and created a completely new direction for one of the oldest-known musical art forms - the art of drums.
Today, because of the complexity of the technique and the setup that it requires, semi-rhythmic drumming is still used by a very small number of drummers (currently less than 30 in the world), in which a single drummer executes two or more rhythms, or rhythm and solo(s) or two or more solos absolutely simultaneously...