Originally choro was played by a trio of flute, guitar and cavaquinho (a small chordophone with four strings). Other instruments commonly played in choro are the mandolin, clarinet, saxophone, trumpet and trombone. These melody instruments are backed by a rhythm section composed of 6-string guitar, 7-string guitar (playing bass lines) and light percussion, such as a pandeiro. The cavaquinho appears sometimes as a melody instrument, other times as part of the rhythm.