The Zheng*) or guzheng is the parent instrument of the Chinese long zither family. Its history can be traced back as far back as the Warring States Period (446 BC-221 BC). It was especially popular in the state of Qin, in the northwest of China and, as a result, some people still refer to the instrument as the qinzheng.
The zheng is basically a plucked half-tube wood zither with movable bridges, over which a number of strings are stretched. The zhengs sound box is constructed of wood, red sandal for its sides and bottom and wutong wood (firmiana platanifolia) for the arched soundboard. According to historical texts, it originally had 12 strings prior to the Han Dynasty, approximately 2,000 years ago. In the 2nd century BC the zheng was described as having twelve red silken strings and high narrow jade bridges. Later, the number of its strings increased to 13 during the Tang Dynasty, then 14 and 15 in the Ming Dynasty, and finally to the present number of 21. Some instrumentalists even prefer to play a 24 or 26-string guzheng.
The modern zheng usually has 21 to 25 strings, made of steel, or metal wound with nylon. It is traditionally tuned to a pentatonic scale (sometimes of a heptatonic one), but many modern scales range from combinations of different pentatonic scales, to diatonic and semi-chromatic scales. The performer uses the right hand to pluck the strings, with the left hand pressing the string on the left side of the bridge to produce vibrato, pitch alterations or slides. In contemporary practice, the left hand often joins the right hand to play a counter-melody. Experimental techniques can include bowed, hammering and preparing the strings.
The guzheng has played an important part of Chinese history as both a court and folk instrument. It is not only a good solo music instrument, its gentle yet crisp sound makes it an excellent instrument for accompaniment. Composers have created various combinations for the guzheng and other traditional Chinese music instruments, such as the erhu, the flute and the pipa. But among them, the union of the guzheng and the xiao, the Chinese vertical flute, has proved the most successful.
*) 古箏, spoken: gǔzhēng. In Japan a variation of Zheng is known as Koto.