Dan Tranh (16-string zither)

The Dan Tranh is also known as Dan Thap Luc or sixteen-stringed zither. The Dan Tranh originates from the ancient capital city of Hue, where women once played it for royalty, and the instrument is still considered a symbol of the city.
Dan Tranh has a long-parallelepiped shape, resembles a bamboo tube that has been sliced vertically in half.. The frame of the instrument has trapezium-shape, 110-120 cm in length. The large end is 25-30 cm in width with holes and to hang the strings. The narrow is 15-20 cm in width with 16 tuning keys on the surface of the instrument. Its surface is made of wootung tree, 0.05 cm thick and arched.

Toward the middle of the sound board there are 16 bridges made of wood or bone tipped with copper for hanging the strings and movable to tune the pitches, thus creating various notes. At the narrower end of the box are sixteen pegs for tuning. The strings are made of metal with different sizes and tuned to the pentatonic scale.

The Dan Tranh sits flat like an autoharp and is plucked using all fingers. Players will usually wear picks made of plastic or tortoise shell on their fingers to facilitate plucking. The sound reverberates through the hollow wooden box below the strings. Sounds can be altered through cupping, pressing or stroking the strings instead of simply plucking.

When playing, artist usually wears finger-nail plectrums on thumb, forefinger and middle finger to pluck. The finger-nail plectrum is made of different materials, such as metal, horn or tortoise-shell.
The music of the Dan Tranh is usually light and full of cheerfulness. The instrument bears some likeness to the japanese Koto, the korean Kayagum, the mongolian Jatac, the chinese Zeng, and the indonesian Kachap, which have 13, 12, 12, 13-16, 7-24 strings, respectively. It is nonetheless an original vietnamese instrument with specific musical characteristics. It is used to accompany poetry recitals and is quite often part of an orchestra or a band playing chamber music, religious music, or accompanying cheo or cai luong drama.
The Dan Tranh is normally played unaccompanied, but it can also be used to accompany a singer, reciting poem or as part of an Tai Tu orchestra, Bat Am company, Nha nhac orchestra and general traditional orchestra. Its timbre is bright and clear and it expresses jubilant and pure melodies. Dan Tranh is rarely suitable with strong and moving characteristics. The range of Dan Tranh includes three octaves, from Do up Do3.

According to Prof. Dr. Tran Van Khe: Dan Tranh of Vietnam derived from Chinese zither and might be from the Tran dynasty or before that. People used it under 9 strings, 15 strings, and 16 strings. These strings are made of silk then copper and now steel. But through seven or eight centuries using it, Vietnamese people created a specific characteristic in fingering techniques, pressing and releasing, and scale. Dan Tranh has become a musical instrument bringing characteristic of Vietnam. Vietnamese people are very fond of using it and it is transmitted from generation to another over 7-8 hundred years, suitable with the aesthetics of Vietnamese people and expressing Vietnamese musical language clearly
If one sound had to be chosen to evoke Vietnam, for many it would be the sound of the Dan Bau as it is one of only two traditional musical instruments of purely vietnamese origin. 
The word "bau" means gourd and refers to the dried gourd fastened to the handle, surrounding the string at the point where it connects to the handle. In the past this gourd may have served as a resonator, but today it survives as a decorative feature. Nowadays the Dan Bau is constructed using hardwood for a frame and softwood for the surface.
According to the "Dai Nam thuc luc tien bien" the first dan bau was made in 1770. 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.
Bau in general consists of 4 components including soundboard (resonator), spout, gourd, string and tuning peg.

The spout is a piece of bamboo or a buffalo horn that is square-framed at the root, while flat and gradually bent at the top. The spout plays an important role in producing sounds of different pitches beyond fundamental overtones of the instrument.
The string runs along the body of instrument. The past silk-made string is now replaced with iron one.

The gourd is made up from a half of a slender-necked gourd. The gourd covers the spout at the very point where the string is hung. The gourd contributes to increase the loudness of sound for the instrument. Nowadays, gourd is usually made from wood and therefore only served as an adornment.

The tuning peg is made from bamboo (if bamboo Bau), or from wood (if wooden Bau). The tuning peg is located at the inside frame towards the bottom of the soundboard. The string goes through a small hole at the end of the instrument's surface and then gets through the tuning peg. In front of such a hole is a bridge to support the string.
The pluck is a pointed stick of bamboo or rattan.

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. But 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 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 notes played by the Dan Bau are smooth, sweet, and captivating. In recent years success has been achieved in amplifying the sound, causing an increase in volume and distance the that the sound carries, while still preserving the quality of the sound.
With soft sounds, Bau is suitably used in serene context. In the past, Bau is the instrument of itinerant singers of Xam genre. Later, Bau also participates in orchestra of Cheo genre, Tai tu style's orchestra, in orchestra serving for declamation, in smaller ensemble or solo performance. There have been many musical pieces exclusively composed for Bau solo, such as Vu Khuc Tay Nguyen (Dance of the Central Highland) by Duc Nhuan, Dong kenh trong (The clear channel) by Hoang Dam, Vi Mien Nam (for the South) by Huy Thuc, and so on.

Among many kinds of monochord of countries all over the world, there are Tuntina of India, Cung of East Africa, Tushuenkin of China. However, none of them can produce such a popular and highly artistic system of overtones as that of Bau of Vietnam. The Dan Bau has been performed on major stages in foreign countries