The practice of Candombe is one of the most characteristic and defining features of Uruguayan popular culture. Created by the slaves brought from Africa in the 18th century and developed by their descendants during a long historical process, it later integrated European immigrants, and now permeates the whole society. The essential component of this tradition is the Candombe drumming, performed by groups of drums playing a distinctive rhythm. All along the year, specially on weekends and public holidays, players meet at specific points to play Candombe marching on the street. One major event convoking thousands of people is the Desfile de Llamadas during Carnival, a parade of traditional groups called comparsas.

The rhythm was also integrated in various forms and degrees into several genres of popular music, like tango and canto popular (folkloristic popular song). Amalgamated with elements of beat, pop and rock music in the late 1960s, it originated candombe beat and later forms of Uruguayan popular music. A detailed account of the historical, sociological and musical aspects of Candombe can be found in [Andrews 2010] and [Ferreira 2007].

Although originated in Uruguay, Candombe discloses its strong African roots in its instruments' topology, its rhythm, and its performance practices. The instrument used in Candombe drumming is the tambor (the generic Spanish word for "drum"), of which there are three different sizes with respective registers: chico (small/high), piano (big/low) and repique (medium). An ensemble of drums is called cuerda, which in its minimal form consists of at least one of each of the three drums but can gather scores of drums.

The drumhead is hit with one hand bare and the other holding a stick that is also used to hit the shell. The group moves forward walking with short steps synchronized with the beats or tactus, and the transference of the body weight from leg to leg while marching constitutes a fundamental pattern, not audible but internally felt [Ferreira 2007].

The first two-lines music score to the right shows the kernel of the rhythmic structure of Candombe: the superposition of the chico pattern and the clave. Lower and upper line represent hand and stick strokes respectively. Following virtually immutable pattern, the chico drum defines the tatum, i.e. the lowest level of pulsation over which the metric structure is built. This basic pulse is usually played at a high rate, typically from 450 to 600 beats per minute (BPM). The periodicity of order four of the pattern is in the range of about 110 to 150 BPM and is perceived as the tactus, although the location of the beat within the pattern can be very difficult to perceive without any further references.

The clave pattern is played by hitting the shell of the drum with the stick, and is played by all the drums before the rhythm patterns are initiated, and also by the repique drum in between phrases. As in Afro-Caribbean and sub-Saharan African music traditions, the clave serves as a mean of temporal organization and synchronization. Its role is twofold: it helps to establish the location of the beat with respect to the chico pattern, and it defines a cycle of four beats (sixteen tatum pulses), thus introducing a higher metrical level.

Two characteristic traits link this configuration with the Afro-Atlantic music traditions: 1) the pattern defining the pulse does not articulate the tatum that falls on the beat, and has instead a strong accent on the second; 2) the clave divides the 16-tatum cycle irregularly (3+3+4+2+4), with only two of its five strokes coinciding with the beat. In this respect, the rhythmic structure of Candombe differs considerably from tonal metric structures, making it difficult to decode for listeners not familiar with it.

The second score adds to the previous set the repique and piano patterns. These two drums exhibit more complexity and variation in their playing, and are shown here simplified to their essentials. It can be seen that, reduced to its rhythmic skeleton, the pattern of the piano drum is congruent with the clave pattern, thus reinforcing the four-beat cycle defined by the latter. The repique has the greatest degree of freedom among the three drums: by exploiting a wide repertoire of complex variations in its rhythmic patterns, it is the main responsible for generating interest, surprise and musical variety in Candombe. It has, however, a primary pattern, shown here in its basic form.