Resources: Instruments: Banjo
The banjo family of instruments have a hide or vellum membrane as a sound-board. Slaves brought the first 'banjos' from Africa to the United States in the 1700s, introducing banjos and banjo music to America. The early banjos often had gourd bodies, almost always had fretless necks, and a various number of strings. With time, wooden and metal hoops replaced the gourd and the nails that secured the hide were replaced by screw mechanism tightens the head across the hoop. (In general, the screws put tension in the head so that it produces a specific note when tapped). Some banjos have open backs; others (like the one pictured) have metal or wooden resonators to amplify the sound. Banjo necks are long and narrow; some have metal frets; others do not have frets. Metal or gut strings fasten in a tailpiece, run over a a bridge, and continue up over the body to slots in the 'nut' (a raised piece of wood at the top of the neck). From the nut, the strings run to tuning pegs in the headstock.The four-string banjo was very popular, replacing the previously fashonable mandolin as the instrument-of-choice among the American public. The four-string banjo, tuned to the same four notes as a mandolin (E, A. D, G) and played with a plectrum, was easy for mandolin players to adopt. Four-string banjos are still used by old-timey and minstrel music (as adopted from black musicians in 19th century minstrel troupes). Four-string banjos do not generally have a resonator or a closed wooden back.
Five-string banjos, common in bluegrass and many other types of folk music, are a modification that Joel Sweeney created in 1833 by adding a string to the instrument. Players either pluck the strings in a three finger sequence (thumb and two fingers, Scruggs-style) or alternately pluck and strum with their thumb and fingers fingers (claw-hammer or frailing). On a five-string banjo, four of the strings run the full length from the tailpiece to the headstock. One extends from the tailpiece to a tuning peg about two-thirds of the way from the tailpiece to the headstock. The strings are numbered 1 to 5, with the 1-string located at the bottom of the instrument when it's held. The 5-string is the short string (also known as the thumb string). The most common tuning for a five-string banjo for bluegrass players is an open G-chord with the strings tuned to D, B, G, D, G.
Hybrid instruments that combine the hide or vellum body of the banjo with the structure and tuning of other instruments also emerged in the early 1900s. These instruments, still available and played, include the bandolin and the banjitar--eight- and six-stringed instruments played like a mandolin and guitar with the tonal qualities of a banjo.