According to the "Dai Nam thuc luc tien bien", the first Dan Bau was made in 1770; yet, many scholars estimate its age to be up to one thousand years older than that. A popular legend of its beginning tells of a blind woman playing it in the market to earn a living for her family while her husband was at war. Whether this tale is based in fact or not, it remains true that the Dan Bau has historically been played by blind musicians. At its first appearance, it was a very simple instrument comprised of a bamboo section, a flexible rod, a calabash or half a coconut. After a process of evolution and improvement, the present form of the Dan Bau is a bit more sophisticated, yet still quite simple. Until recent times, its soft volume limited the musical contexts in which it could be used. The Dan Bau, played solo, is central to Vietnamese folk music, a genre still popular today in the country. Its other traditional application is as an accompaniment to poetry readings.
Music from Dan Bau
The word "monochord" means literally "one string." In the monochord, a single stringsis stretched over a sound box. The string is fixed at both ends while a movable bridge alters pitch. Originally, the Dan Bau was made of just 4 parts: a bamboo tube, a wooden rod, a coconut shell half, and a silk string. The string was strung across the bamboo, tied on one end to the rod, which is perpendicularly attached to the bamboo. The coconut shell was attached to the rod, serving as a resonator.
As usually seen, Dan Bau consists of an oblong box-shaped sound board, slightly narrower toward one end, with a slightly warped top made of unvarnished soft light wood, sides made of hard wood, and a bottom of light wood pierced with holes for better sound. At one end of the sound board is a flexible bamboo rod that goes through a dried calabash whose bottom end has been cut out before being fixed on the sounding board. At the other end of the sounding board is a peg made of wood or metal used for tuning. The metal string is attached to the rod and to the peg. The pluck is a pointed stick of bamboo or rattan. Although having only one string, it can emit all the sounds in the pentatonic scale. The eight notes of Vietnamese music give modulations of greater amplitudes than those obtained by any other single-stringed instrument in the world. The Dan Bau is usually tuned to the note C. It uses harmonies (or overtones). When playing, the musician plucks the string while touching it lightly with the side of his hand at a point producing a harmony. However, because the flexible rod causes the tension of the string to vary, the pitch may be made to rise or fall, the note may be lengthened or shortened, and trills may be played. The technique involving the fingers of the left hand includes vibrating, pressing, alternate pressing and releasing. The Dan Bau may be played on a scale consisting of third-tones or even quarter-tones. The notes played by the Dan Bau are smooth, sweet, and captivating.
In recent years, Dan Bau is made very carefully to ensure aesthetic and sound quality. When played in public, it is often used with an electronic amplifier. Success has been achieved in amplifying the sound, causing an increase in volume and distance that the sound carries, while still preserving the quality of the sound. The instrument is played solo or to accompany a poetry recital. During recent years, it has taken a role in orchestral accompaniment to Cheo and Cai luong opera. The Dan Bau has been performed on major stages in foreign countries.
Playing the Dan Bau is simple but requires a great deal of precision. The pinky of the right hand gently taps the string at one of seven commonly used nodes while the other fingers pluck the string using a long plectrum. With the left hand, the player can push the flexible rod towards the instrument using the index finger to lower the pitch of the note, or the player can pull the rod away from the instrument with the thumb to raise the pitch of the note. This technique is used both to play notes not available at a node as well as to add vibrato to any note.