Tumbao

In music of Afro-Cuban origin, tumbao is the basic rhythm played on the bass. In North America, the basic conga drum pattern used in popular music is also called tumbao. In the contemporary form of Cuban popular dance music known as timba, piano guajeos are known as tumbaos.

The tresillo pattern is the rhythmic basis of the ostinato bass tumbao in Cuban son-based musics, such as son montuno, mambo, salsa, and Latin jazz.

Often the last note of the measure is held over the downbeat of the next measure. In this way, only the two offbeats of tresillo are sounded. The first offbeat is known as bombo, and the second offbeat (last note) is sometimes referred to as ponche. The following example is written in cut-time (2/2).

Arsenio Rodríguez's group introduced bass tumbaos that have a specific alignment with clave. The 2-3 bass line of "Dame un cachito pa' huele" (1946) coincides with three of the clave's five strokes.Listen to a midi version of the bass line for "Dame un cachito pa' huele." David García Identifies the accents of "and-of-two" (in cut-time) on the three-side, and the "and-of-four" (in cut-time) on the two-side of the clave, as crucial contributions of Rodríguez's music. The two offbeats are present in the following 2-3 bass line from Rodríguez's "Mi chinita me botó" (1944).

The two offbeats are especially important because they coincide with the two syncopated steps in the son's basic footwork. The conjunto's collective and consistent accentuation of these two important offbeats gave the son montuno texture its unique groove and, hence, played a significant part in the dancer's feeling the music and dancing to it, as Bebo Valdés noted "in contratiempo" ['offbeat timing']—García (2006: 43).

Moore points out that Rodríguez's conjunto introduced the two-celled bass tumbaos, that moved beyond the simpler, single-cell tresillo structure. This type of bass line has a specific alignment to clave, and contributes melodically to the composition. Rodríguez's brother Raúl Travieso recounted, Rodríguez insisted that his bass players make the bass "sing." Moore states: "This idea of a bass tumbao with a melodic identity unique to a specific arrangement was critical not only to timba, but also to Motown, rock, funk, and other important genres." In other words, Rodríguez is a creator of the bass riff.

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