Composite rhythm



Audio: composite rhythm (0:10)

Composite rhythm
Figure: composite rhythm

composite rhythm plays composite rhythms on bongo drums and claves. Tempo is kept by claves. The composite rhythm figure, the score, shows accented beats on the high bongo and unaccented beats on the low bongo played in the following rhythms:

  • Bar 1: 2/4 rhythm played as (1+1)/4.
  • Bar 2: 3/4 rhythm played as (2+2+2)/8.
  • Bar 3: 6/8 rhythm played as (3+3)/8.
  • Bar 4: 4/4 rhythm played as (3+3+2)/8.
  • Bars 5-6: two bars of 4/4 rhythm played as (3+3+3+3+2+2)/8.

Composite rhythm is a rather vague term. Some commentators use it to describe complex rhythm, some use it to describe polyrhythm, and others use it to describe the sum of different rhythms played by individual instruments. We use the term to mean a single rhythm constructed from two or more shorter rhythms.

A composite rhythm can be constructed top down or bottom up. The top down approach takes a rhythm and breaks it up into groups of beats, the bottom up approach adds groups of beats together. The terms additive and divisive rhythm are used to distinguish between these two approaches. It does not matter which approach you use, the outcome is the same, a composite rhythm.

Any time signature can be considered a composite time signature. Sometimes there is little benefit in doing so, such as the 2/4 meter shown in the first bar of composite rhythm which can theoretically be interpreted as a composite (1+1)/4 meter. More interesting are the examples of 3/4 and 6/8. These time signatures can be ambiguous and composite rhythm is a way of making them unambiguous. 3/4 represents two composite rhythms: (1+1+1)/4, not shown in composite rhythm, and (2+2+2)/8, shown in the second bar of composite rhythm. However, (2+2+2)/8 is not the same as 6/8 because this is interpreted, by convention, as compound duple meter, which is easier to understand as a composite (3+3)/8 meter, as shown in the third bar of composite rhythm.

Another powerful advantage of composite rhythm is that it allows beats to be grouped together in a mixture of twos and threes. For example, 4/4, simple quadruple meter is normally interpreted as a composite (1+1+1+1)/4 or (2+2+2+2)/8 rhythm. An alternative is to consider 4/4 a composite (3+3+2)/8 meter, as shown in the fourth bar of composite rhythm. This composite rhythm is, in fact, occasionally notated 8/8 to emphasise that it is a composite (3+3+2)/8 meter instead of the usual quadruple meter.

A further benefit of composite rhythm is that it can span multiple bars. For example, two bars of 4/4 can be interpreted as a composite (3+3+3+3+2+2)/8 meter, as shown in the fifth and sixth bars of composite rhythm.

Composite rhythm is an extremely useful tool for writing rhythm. It clarifies ambiguity in a meter, allows greater flexibility in rhythm patterns, and enables you to write intricate rhythms from a sequence of shorter and simpler rhythms.