Gayageum
The gayageum or kayagum (in Korean 가야금) is a traditional Korean plucked zither with 12 strings, though some more recent variants have 18, 21 or 25 strings. It is probably the best known traditional Korean musical instrument. It is similar with other Asian instruments like Chinese "guzheng", Japanese "koto", Mongolian "yatga", Vietnamese "đàn tranh", Sundanese "kacapi" and Kazakh "jetigen". History. Pungryu gayageum (beopgeum, jeongak gayageum). According to the "Samguksagi" (1146), a history of the Three Kingdoms of Korea, the "gayageum" was developed around the sixth century in the Gaya confederacy by King Gasil (also known as Haji of Daegaya ) after he observed an old Chinese instrument. He ordered a musician named Wu Ruk to compose music that could be played on the instrument. The original name was "gayago"(or "gayatgo") and later" gayageum". The "gayageum" was then further improved by Wu Ruk during the reign of Jinheung in the Shilla dynasty. The ancient "gayageum" of King Gasil was called by several names, including "beopgeum" (law-zither, 법금), "pungnyu" (elegance, 풍류), or "jeong-ak" (right music, 정악) "gayageum". It is normally associated with accompaniment for court music, chamber music, and lyric songs. This type of "gayageum" has a wider spacing between  the strings and plays slower-tempo music such as "Yeongsan hoesang" and "Mit-doduri". Sanjo gayageum. The "sanjo gayageum" is believed to have evolved in the 19th century with the emergence of "sanjo" music, which literally means "scattered melodies", a musical form that involves fast tempos and some improvisation. The "sanjo gayageum" version of the instrument has closer string spacing and a shorter length to let musicians play the faster passages required for "sanjo". The "sanjo gayageum" is now the most widespread form of "gayageum". All traditional "gayageum" use silk strings, though since the late 20th century, some musicians use  nylon. Modern gayageum. Modern versions of the "gayageum" with more strings often use nylon-wrapped steel strings, similar to those used for the Chinese "guzheng". Brass strings have also been introduced to produce a louder sound, which is preferred for accompanying dance. To play modern music, "gayageum" with a greater number of strings have been developed, increasing the instrument's range. "Gayageum" are available with 13, 17, 18, 21, 22, or 25 strings, though instruments with more strings are available custom-made. The 21-string gayageum is normally found in North Korea. Playing method. The gayageum is traditionally played when  sitting on the floor with crossed legs, the head of the instrument resting on the right knee and the tail resting on the floor. When played whilst seated on a chair or stool, the tail end is usually placed on a special fold-out stand, similar to a camp-stool, or another chair/stool. For modern "gayageum", they may be placed on a special stand with the player seated on a chair behind the instrument. The North Koreans usually play whilst seated on a chair, but they do not use a stand of the tail end. Instead, the "gayageum" has  detachable legs that are fixed into the end to raise the tail high enough. The "gayageum" is played with both right and left hands. The right hand plucks and flicks the strings close to the bridge of the gayageum, whilst the left hand pushes the strings on the left side of the bridges to raise the pitch and adds vibrato and other ornamentation. Tunings and modes. The "gayageum "can be tuned to a variety of pitches depending on use, though no standard exists as to what exact pitches they should be tuned. They include: When noted in staff notation, however , the pitch series is usually transposed as the following, regardless of the actual pitches tuned on the strings: This is to avoid switching between the bass and treble clefs to make reading the music easier. Traditionally, three modes are used: Construction. The "beobgeum gayageum" is 160 cm long by 30 cm wide by 10 cm deep. Its body is made of a single piece of paulownia wood. The resonator chamber is hollowed out of the piece of paulownia. The "sanjo gayageum" is about 142 cm long by 23 cm wide by 10 cm deep. The soundboard is made of paulownia , but the sides and back are of a harder wood such as chestnut or walnut. On the soundboard, "anjok" (movable bridges) support the strings. These bridges move to adjust the tuning and intonation. The strings enter the top of the body from "tolgwae" (string pegs) beneath. At the other end, the strings wind around loops at the end of thick cords, which pass over the nut then looped through holes at the bottom of the instrument and secured, and then the cords are all tied in a decorative coil. The left hand presses the strings to raise the pitch, and  finger movements perform various movements such as shaking, bending, and vibrating the strings. The right hand plucks or strums the strings. The "gayageum's" tone is soft, delicate, and subtle. Legend says the instrument was first made by King Gasil in the Kaya Kingdom around the sixth century, and was further developed by Ureuk in the time of King of Jinhung in the Silla dynasty. According to some evidence, however, it dates to a much earlier time than the Silla dynasty. Recent archaeological excavations in the Kwangsan areas in Jeolla-namdo Province revealed fragments of a "gayageum" from around the  first century BCE. The "gayageum" is employed in different types of music, leading to variations of the instrument, including the following: Music. Sanjo and folk. The six or more schools of the "gayageum sanjo" include Seong Geum Yeon, Kim Juk Pa, Kim Yoon Deok, Kang Tae Hong, Kim Byeong Ho, and Choi Ok Sam schools. Contemporary. Contemporary music composers have been creating modern music for the "gayageum". Hwang Byung Ki composed "Forest" as a first modern "gayageum" piece, Sungcheon Lee created 21-string "gayageum" and new pieces. Beomhoon Park composed the "gayageum" concerto "New Sanjo" (새산조) for 25-string "gayageum , and following generation's composers and western musicians have been composing modern music for it.