High Quality Content by WIKIPEDIA articles! A rhythm section is the musicians in a popular music band or jazz ensemble who perform the accompaniment musical parts which establish the rhythmic pulse of a song or musical piece, and who lay down the chordal structure and bassline. The instruments used in a rhythm section vary according to the style of music and era. Modern pop, rock and jazz bands usually have a rhythm section which consists of a drummer, a bass player, and one or more chordal instruments (e.g., piano, guitar, etc.). The term "rhythm section" may also refer to the instruments in this group.