Rhythm section

A rhythm section (also called a backup band) is a group of musicians within a music ensemble or band who provide the underlying rhythm and pulse of the accompaniment, providing a rhythmic reference and "beat" for the rest of the band. Many of the rhythm section instruments, such as keyboard instruments and guitars, are also used to play the chord progression upon which the song is based. The bass instrument (either double bass or electric bass, or another low-register instrument, such as synth bass, depending on the group and its style of music) plays the low-pitched bassline that supports the chord progression, typically by emphasizing the roots of the chords (and to a lesser degree the fifths and thirds of the chords).

The term is common in modern small musical ensembles, such as bands that play jazz,country, blues, and rock. In modern rock music, a rhythm guitarist specializes in rhythmic and chordal playing (as opposed to the melodic guitar solos and lead melody lines played by the lead guitar), often repeating quaver (eighth-note), half note or whole note chords. In the louder genres, such as hard rock, heavy metal and punk rock, rhythm guitarists often play power chords with distortion. Rhythm guitarists often strum open chords in pop, rock, country and folk music and play barre chords in many pop and rock styles.

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