The Beatles: Rock Band allows players to perform simulated rock music by providing up to six players with the ability to play three different controllers modeled after music instruments (a guitar controller for lead guitar and bass guitar gameplay, a drum controller and up to three microphones for vocals). Players simulate the performance of rock music by using their controllers to play scrolling on-screen notes.[3][4] For lead and bass guitar, this is accomplished by holding down colored buttons mimicking guitar frets and pushing the controller's strum bar; for drums, this requires striking the matching colored drumhead, or stepping on the pedal to simulate playing bass drum notes. A "Lefty" mode allows left-handed people to play, by switching which colour the beats are given. When singing vocals, the player must sing in relative pitch to the original vocals. A pitch indicator displays the singer's accuracy relative to the original pitch. For songs with multi-part vocals, players need only to stay in tone with the lead singer to score points and keep their performance meter up, but players earn additional scoring bonuses when they successfully complete phrases in harmony.