Guqin structure
This article is a description of the qin as it is today, and indeed has been since at least the Tang dynasty (+618 ~ +907). It does not cover the development of the qin into its present form or minor variations in its outward shape, both of which will be covered in separate articles, and it ignores the rare instruments made of metal or stone.
A qin is a seven stringed zither. According to Needham (Needham, p. 130n.), basing himself on the Sachs system for classifying musical instruments, a guqin "may be described as a half-tube zither [...], for it consists of a flat elongated board concave below and convex above, upon which are mounted the silk strings."
Van Gulik, preferring to call the qin a lute because of the associations which both have with "all that is artistic and refined" (van Gulik 1969, p. viii), describes a qin in some detail:
"The body of the lute, which functions as sounding-box, consists of two boards of a special kind of wood, superimposed one upon the other [...]. The upper part, made of t'ung wood, is concave, while the lower part, made of tzu wood, is flat, with two openings for transmitting the sound. Over this sounding box the seven strings are strung. They are all of different thicknesses: that farthest from the player and giving the lowest tone is the thickest, while that nearest the player and giving the highest tone is the thinnest of all. On the left the strings, in two groups of three and four, are fastened to two wooden knobs driven into the bottom board. On the right side each string ends in a peculiar knot. It passes through a loop of silk, which can be twisted by turning a tuning peg made of wood, ivory or jade. The knot prevents the string from slipping when it is tuned by twisting the loop. On the right side, where the loops pass through holes in the body of the sounding box, a bridge is set up, made of a special kind of hard wood (usually red sandalwood, tzu-t'an [traditional and simplified characters 紫檀 Hanyu Pinyin: zitan; Tongyong Pinyin: zih-tan]), glued to the upper board. A little to the left of this bridge the fingers of the right hand, except the little finger, pull the strings. The four fingers of the left hand stop the strings in various places, the hand being guided by thirteen studs made of some precious metal or of mother-of-pearl, and embedded in the varnish along the front side of the sounding box. In playing, the performer lays the lute on a special table, so that the side where the tuning pegs are is at his right. He sits on a comparatively high seat, preferably without elbow rests, since these might interfere with the free movement of the arms." (van Gulik, p. 4)
The body of the qin A qin is about 1.20 metres long, about 20 cm wide at one end and about 15 cm at the other. It is made of two boards. The upper board, traditionally made from paulownia [van Gulik’s t’ung, traditional and simplified character 桐 Hanyu Pinyin and Tongyong Pinyin: tong] or firmania of sterculia species (Picard, p. 126), is convex outside and concave inside. A very crude analogy would be a short length of flattish guttering turned upside down. The lower board, traditionally made from catalpa [van Gulik’s tzu, traditional and simplified character梓Hanyu Pinyin: zi; Tongyong Pinyin: zih] which is harder and denser than the paulownia, is basically flat, but in older instruments its outer-side may be slightly convex. The two boards are nailed or glued (or nailed and glued) together along their outer edges to form a long, sounding chamber 2~3 cm high at its highest point. Inside the sound cavity sound pegs, generally two, connect the upper and lower boards.
The maximum external height of the sounding box is about 5 cm.
The upper board need not be a single piece of wood: "bai na qin" (hundred patch qin) have upper boards made up of a number of smaller pieces of wood carefully shaped and then glued together. The small pieces are hexagonal with one pair of parallel sides slightly longer than the others, the long pair of sides being parallel to the long axis of the qin. The pictures of bai na qin in Gugong Guqin (Zheng, pp. 170-175,) show the side faces of the small pieces of wood as being glued together for their whole depth, but in recent years at least one maker has made bai na qin with the small pieces of wood being glued together only along their the upper halves of their sides, the lower halves being planed at an angle. It is not clear whether controlled tests have been done to measure the differences, if any, of the sound produced by the two methods.
It must also be mentioned that modern qin rarely make use of the traditional woods. Instead fir is used but it must be old. The best makers now use timber from the pillars of demolished ancient buildings, or even from exhumed coffins.
There is a hardwood bridge about 10 cm from the wider and of the qin and a hardwood insert at the narrower and. There are also two short feet 30~40 cm from the narrower end.
There are generally two oblong sounding holes in the bottom board, though some qin have a single round or square sound hole or two holes of different shapes.
[Lacquer] To provide a hard, smooth playing surface the body of the qin is covered with a number of thin layers of a lacquer by mixing urushiol and a thinning agent, nowadays turpentine. Traditionally the inner layers consisted of the lacquer mixed with a powder made by grinding roasted deer antlers and applied either directly onto the wood or onto linen cloth which was glued to the wood. The size and number of the powder particles reduced as more layers were added, until finishing layers were pure lacquer. In early days the lacquer was mixed with cinnabar to give a red colour, but in later times a dark, brown to black colour was preferred. Sometimes a mixture of powdered semi-precious stones, or even copper or gold dust, was mixed into the lacquer to give an attractive appearance and, it was said, improve the instrument's tone. When applied the lacquer was cured by placing the qin in a warm humid place. Finally it was polished not only to give the most comfortable playing surface but also to ensure that the playing surface was shaped correctly to avoid the production of unwanted buzzing sounds.
[Inlays] Thirteen small discs are laid into the lacquer along the outer edge of the qin. They show the positions of the main harmonics and help identify the positions of stopped notes.
References Needham, J: Science and Civilisation in China, Vol. IV:1 Physics, p. 130, footnote a. Cambridge, Cambridge University Press, 1962
Van Gulik: The Lore of the Chinese Lute. Revised edition, Tokyo, Sophia University and Tuttle, 1969
Picard. F. La musique chinoise. Editions You-Feng, Paris, 2003
Zheng, M Z. Gugong Guqin, Beijing, Forbidden City Publishing House, 2006.