From The Art and Popular Culture Encyclopedia
Polyrhythm is the simultaneous sounding of two or more independent rhythms. Polyrhythm in general is a nonspecific term for the simultaneous occurrence of two or more conflicting rhythms, of which cross-rhythm is a specific and definable subset.—Novotney (1998: 265)
Polyrhythms can be distinguished from irrational rhythms, which can occur within the context of a single part; polyrhythms require at least two rhythms to be played concurrently, one of which is typically an irrational rhythm.
In popular music
Nigerian percussion master Babatunde Olatunji arrived on the American music scene in 1959 with his album Drums of Passion, which was a collection of traditional Nigerian music for percussion and chanting. The album stayed on the charts for two years and had a profound impact on jazz and American popular music. Trained in the Yoruba sakara style of drumming, Olatunji would have a major impact on Western popular music. He went on to teach, collaborate and record with numerous jazz and rock artists, including Airto Moreira, Carlos Santana and Mickey Hart of the Grateful Dead. Olatunji reached his greatest popularity during the height of the Black Arts Movement of the 1960s and '70s.
Afro-Cuban music makes extensive use of polyrhythms. Cuban Rumba uses 3-based and 2-based rhythms at the same time, for example, the lead drummer (playing the quinto) might play in 6/8, while the rest of the ensemble keeps playing 2/2. Afro-Cuban conguero, or conga player, Mongo Santamaría was another percussionist whose polyrhythmic virtuosity helped transform both jazz and popular music. Santamaria fused Afro-Latin rhythms with R&B and jazz as a bandleader in the 1950s, and was featured in the 1994 album Buena Vista Social Club, which was the inspiration for the like-titled documentary released five years later.
Among the most sophisticated polyrhythmic music in the world is south Indian classical Carnatic music. A kind of rhythmic solfege called konnakol is used as a tool to construct highly complex polyrhythms and to divide each beat of a pulse into various subdivisions, with the emphasised beat shifting from beat cycle to beat cycle.
Common polyrhythms found in jazz are 3:2, which manifests as the quarter-note triplet; 2:3, usually in the form of dotted-quarter notes against quarter notes; 4:3, played as dotted-eighth notes against quarter notes (this one demands some technical proficiency to perform accurately, and was not at all common in jazz before Tony Williams used it when playing with Miles Davis); and finally 3/4 time against 4/4, which along with 2:3 was used famously by Elvin Jones and McCoy Tyner playing with John Coltrane.
The Beatles used polyrhythm in their 1968 song "Happiness Is a Warm Gun"(from the White Album). The song also changes time signature frequently. The Beatles use polyrhythm again on Abbey Road's "Mean Mr. Mustard".
Jimi Hendrix had the distinct ability to play polyrhythmic melodies on his guitar during live concerts and jam sessions. This ability was facilitated by the impressive length and size of his hands, and his unorthodox fretting method, in which he would maintain rhythm and lead melodies while using his thumb to fret underlying basslines. Examples are live concerts from 1968 to 1970, in particular a performance of "Killing Floor" live at Winterland 1968, an Improvisation during Woodstock 1969, a solo guitar jam for his song titled "Valleys of Neptune", among several other recordings.
Frank Zappa, especially towards the end of his career, experimented with complex polyrhythms, such as 11:17, and even nested polyrhythms (see "The Black Page" for an example). The metal bands Meshuggah, Nothingface, Periphery, Threat Signal, Lamb of God, Textures and TesseracT also use polyrhythms in their music. Contemporary progressive metal bands such as Tool, Animals as Leaders and Dream Theater also incorporate polyrhythms in their music, and polyrhythms have also been increasingly heard in technical metal bands such as Ion Dissonance, The Dillinger Escape Plan, Necrophagist, Candiria and Textures. Much minimalist and totalist music makes extensive use of polyrhythms. Henry Cowell and Conlon Nancarrow created music with yet more complex polytempo and using irrational numbers like pi:e.
Nine Inch Nails front man Trent Reznor uses polyrhythm frequently. One notable appearance is in the song "La Mer" from the album The Fragile. The piano holds a 3/4 riff while the drums and bass back it with a standard 4/4 signature. Talking Heads’ Remain in Light used dense polyrhythms throughout the album, most notably on the song "The Great Curve".
Megadeth frequently tends to use polyrhythm in its drumming, notably from songs such as "Sleepwalker" or the ending of "My Last Words", which are both played in 2:3.
- Ewe music
- Beat (acoustics) - another example of the same effect (mathematically), but with two continuous waves rather than a hit of the instrument only at every peak and trough of either wave.
- Peter Magadini (2001). Polyrhythms: The Musicians Guide. ISBN 0-634-03283-6. Polyrhythm reference book.
- Peter Magadini (1993). Polyrhythms For The Drumset. ISBN 0-89724-821-X. Study in polymetric independence for drummers.