A banjo roll is a method of keeping time by plucking eighth notes in a repeated pattern. There are both forward and backward (reverse), mixed and forward-reverse banjo roll picking patterns. Each banjo roll is picked by the players thumb, index and middle finger in a style that has become known as the Earl Scruggs bluegrass picking style. The banjo is commonly played in open tunings, allowing the roll to begin on any string. The roll pattern is used to break up the rhythm of the song and adds a counter-melody to the music.
Commonly used while playing bluegrass-style music, the banjo roll provides the music with an uneven flow that dissolves the metronomic feel of the melody. This is especially helpful when playing with a large, stringed ensemble. The banjo roll can be played continuously, through an entire song, in either a single note or in changing notes to provide a subtle background to any type of music, at any tempo. This style of picking is often done by combining different types of banjo roll styles with occasional back-up licks being added into the mix. While there is no set standard for picking a forward roll, the pattern is set in stone and the roll must contain eight notes.
Unlike the typical method of strumming a guitar, when all strings are struck by the pick on a single strum, the banjo roll involves only three strings being picked in a specific order. Due to the stings of the banjo being picked at eighth notes, the banjo is commonly picked at twice the speed of the other stringed instruments during a typical four-count melody. While only three strings are being picked in a typical roll, the player has the option of switching which strings are being picked. This ability to improvise the roll in the midst of a picking session is what gives the banjo roll such a prominent sound among all of the stringed instruments.
Many beginning banjo players start out by playing a single forward roll in an open tuning for the duration of a song. This method, while not difficult, lends the signature banjo sound to the music. As the player's talent evolves, reverse and mixed rolls will be added into the music, eventually building up to rolls in differing chords. Eventually, the player will become adept at changing chords and the type of banjo roll several times during a song, giving the selection of music what has become known as the Scruggs bluegrass sound.