Studio musicians are musicians that perform with a band or solo artist in the studio, but they are not official members of the group. Your responsibilities may include performing at a specific gig or audio session, playing your instrument to help people complete their record, and improvising when necessary to complete or perform a song. Other duties include helping with the arrangement of a song, assisting musicians with studio and live rehearsals, filling in for other musicians when they are not available for a performance, helping the producer and sound engineer with mix-down and recording, and helping to set up musical equipment.