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Chinese guqin has a long history, and it is still treasured in the national museum and folk Qin of Tang, Song, Yuan and Ming dynasties. However, due to thousands of years of social unrest. Due to the war, there were only a few guqin handed down from generation to generation, especially during the Cultural Revolution, which was an unprecedented disaster for guqin. Nowadays, few guqin have survived. For piano fans, it is even more rare to see a handed down piano with excellent internal and external (internal sound quality and external appearance). The existence of guqin is of certain significance to archaeology, lacquerware, wood industry, acoustics, piano aesthetics, weights and measures, new piano making and performance. However, due to the long life of guqin, man-made and natural damage, many old guqin are incomplete and rarely complete. In order to preserve these cultural heritages permanently, it is very important to repair them in time and correctly. Because most of the guqin to be restored has a history of more than 100 years, it belongs to the category of cultural relics. The age, broken lines, foundation and inscriptions involved in the restoration work are absolutely different from those of Pipa and Zheng. Damaged parts of other musical instruments can be replaced, but guqin can't. The restoration of guqin is not only a musical instrument, but also a cultural relic. Due to the lack of literature in this field as a reference for piano restoration, the author has been groping for a summary while making new pianos for more than ten years, and has repaired a considerable number of pianos handed down from generation to generation, and made repair notes for each piano one by one. These restored pianos have been repaired and improved to a considerable extent on the surface and inside. Friends at home and abroad encouraged me to sum up and spread my piano practice experience. So I chose a short summary and sorted it into two parts, namely, the repair scheme and the repair example, in order to attract more attention. Please criticize and correct me.
First, the repair plan:
Qin Shen 1- 1.
This old piano has been filed, so we shouldn't rush to do it. We need to carefully examine the piano "Treatment Based on Syndrome Differentiation". Discrimination: that is, analysis and identification; Symptoms: symptoms and phenomena; Discussion: discussion and consideration; Treatment: It's a treatment plan.
It is realistic to treat pre-disease and hand disease, and the theory of syndrome differentiation and combination is flexible. What methods and materials should be used for treatment and repair? It is necessary to brew repeatedly according to the individual characteristics of each piano, establish the best scheme, and make targeted and symptomatic repairs.
Through practical operation, the author summarizes five methods of practicing the piano:
(1) Dating: According to factors such as lacquer wood color, lacquer wood quality, broken line, material, modeling style, inscription, etc. , combined with "color and sound quality" to judge its production age.
(2) Look at its type: the integrity and damage degree of the piano body and paint layer and the bonding strength between them.
(3) Check its color: paint color, wood color and accessory color.
(4) Distinguish its sounds: crackling sound, hard bottom sound, three virtual and four real sounds, and slapping the strings. The sound of the piano is hollow.
(5) Other qualities: the piano material is soft and hard, the paint layer is thick, the weight of the piano body is heavy, and the accessories are old and tender.
1-2, glue repair
If the upper and lower plates of the piano are degummed and cracked or the accessories are loose, glue should be applied first. Method:
(1) Brush, remove and blow to remove floating ash (the old ash in the piano cavity need not be wiped off).
(2) Use a knife, thin steel sheet and fine shavings to remove the old glue.
(3) Apply the fish glue evenly on the glue surface while it is hot (the glue piano works best in sunny days with the temperature of 15-25 degrees, which prevents the glue from rotting in summer and reduces the bonding strength in winter), and tie it with a rope. Use a clip. The clip must be lined with rubber blocks to prevent the piano from sinking. Use a rope to pad the music to prevent the rope from printing. After the old piano with loose and rotten texture is coated with glue, it is most prone to paint collapse (paint layer sag) and dents after the rope clip is attached. Be sure to check it very carefully in advance, mark the weak parts and carry out special treatment to prevent the above symptoms.
1- 3 staggered wood
If the piano body is damaged due to splitting, it is necessary to find wood with similar texture, wood grain and age from the old materials, and repair it according to the method of Yin and Yang in place (see Musical Instrument Magazine 9 1 third issue, the author's essay "Yin and Yang Theory and Guqin"). )
The principle of repairing is to keep the original appearance of the piano as much as possible, but sometimes the damaged part will become bigger and bigger because of looseness and decay, and even cause uncontrollable situations. I own a harp with paulownia on the surface, miscellaneous wood on the bottom and antlers painted with gray pigment. I have seen several broken lines, but the panels have been corroded, and there is only one layer of paint left in some places. When I practiced the piano in my early years, I knew little, operated blindly and was in a dilemma. 【 This piano was restored in the autumn of 1998. Using the method of leaving skin instead of wood, the sound quality is still good after repair and the effect is satisfactory. June 5438+February 2000 new note]
Loose parts must be reinforced first, and then repaired in order.
1-4 bottom ash repair
In the practice of restoration, I found that the main components of the bottom ash used in Qin before the Ming Dynasty were mostly antler ash or babao ash, and there were few tile ash. After the Ming Dynasty, the Qin (Qing Qin) was dominated by tile gray background, and the production technology and sound quality were mostly poor, which was the period when the production technology and sound quality of guqin declined. Relatively speaking, the piano before the Ming Dynasty is easy to repair, and the piano after the Ming Dynasty is difficult to manage, all because the tile ash can't stand the raw lacquer process.
Grey repair method: antlers with paint layer falling off shall be treated differently according to the thickness of paint layer. Thick bottom ash: the ancients divided it into three layers: coarse, medium and fine. It is better to operate according to the ancient method today. On the one hand, it conforms to the raw lacquer process, on the other hand, it is beneficial to the sound quality. The fineness of antler ash and coarse ash I use is 60 mesh, medium ash is 80 mesh, fine ash is 100 mesh, and very fine ash is 120 mesh (very fine, so it is not allowed to fall into medium coarse ash or impurities, otherwise it will be easy to scratch after fine patching and scraping. )
Thin bottom ash, supplemented by fine ash. Tile-grey piano can be supplemented with ordinary magnetic powder and mineral powder. The principle of filling ash is to keep it as original as possible. Try not to expand the repair area, so there must be a variety of specifications of ash knives (ash scraping knives), and sometimes dozens of various sizes need to be prepared for selection. The key point of restoration is the part within the chord road and above four emblems, as long as it remains the original appearance and is no longer damaged. Repairs other than chords also need to be treated differently, because they do not refer to the contact part, and the principle of repair is the same as that of the four emblems or above. Woodcarving craft works in common ancient buildings, with the so-called cultural relics protection paint thickening year by year, people's eyebrows and landscapes are gradually buried, and the spirit of the works is lost, which can be cited as the ring of guqin restoration.
1-5, brake string compensation
Many old pianos have problems with bending and bowing. If the sound quality is normal and the appearance is good, if it is preserved as a cultural relic, there is no need to adjust the brake sound. If the historical traces on the piano are destroyed in order to repair an old piano with average sound quality, it will not be worth the candle. If you play, you might as well add a new piano with better sound quality. But for an old piano with good sound quality and braking sound, it is still worth repairing. The repair scope should be controlled within the chord line. Must be carefully measured before repair, correct addition and subtraction. If you add and subtract repeatedly, it will do more harm than good.
1-6, topcoat repair
The lacquer color of Qin terracotta warriors handed down from ancient times is more mysterious than Zhu. The repair of lacquerware is difficult to achieve the harmony between the new repair and the original color. Even in the lacquer industry, although experienced masters can reconcile the old and new paint colors, through refraction observation, the old and new are clear at a glance. The unification of colors is so difficult, how to make up the guqin topcoat? However, we piano people don't care much about this problem, and sometimes we use different paint colors to make up for it. After makeup, the colors are mixed harmoniously, and the spots are separated, which is more beautiful. The color of the pigment is mixed with natural excesses and clouds, so it is forbidden to cut tofu blocks with a knife. [New Note in June 5438+February 2000: The author's research and interview found that many cinnabar colors handed down from Qin Dynasty were mostly made by Qin people or craftsmen during the late Qing Dynasty and the Republic of China. Personally, I think it is better to refer to the basic sounds of the piano you have repaired. ]
My practical experience, the coordination of top coat color, first of all, there must be a bottom ash supplement that is coordinated with the original color, and then there will be harmony between the old and new paints. For the black piano, the primer is mostly dyed black with raw lacquer; Zhu Se Qin is mostly made of cinnabar. Through constant comparison, it is found that these two colors are closest to the Zhu Xuan color of Old Qin. Although the color depth is inevitable after complementary color, the tone is consistent and harmonious.
The last process is wiping. The traditional method is to use silk or old cotton balls. I use nylon silk, which is better than the former.
1-7, annex supplement
The accessories involved are: Yueshan, Lu Cheng, Longjiao, Guanjiao, Rubber Bracket, Bracket Horn, Goose Foot, Fenzi and Fenchi Bottom Wood. According to my experience in making a new piano, the unification of materials for each piano body accessory is not only a matter of harmonious and beautiful colors, but more importantly, the unification of materials is conducive to improving the sound quality of the piano. Therefore, in the restoration of old pianos, the unity of materials and colors should be considered as much as possible. The accessories of Laoqin are mostly rosewood, copper rough, iron powder, rosewood and ebony, followed by hardwood such as cedar, rosewood, jujube and iron oak (mostly dyed), which are excellent materials for making accessories. The accessories of the modern new piano are mostly rosewood. The above five hardwoods have loose, transparent, crisp and bright music, while the latter and rosewood have no sound. I think the new piano is not as good as the old one. The reason for this situation is closely related to the different accessories used.
Supplementary accessories should be unified with the original materials according to the possibility of the piano body. If the original fittings are poor, high-quality fittings can be replaced according to the specific situation, especially Yueshan, Gui Long, Gingival Support and Yanzu. [June 5438+February 2000] The new piano is inferior to the old one. ""New note: After more than 20 years of tempering, several piano manufacturers in Chinese mainland have made this kind of piano, and its sound quality has surpassed that of Qin Ming. It seems that it is expected to catch up with the Tang and Song Dynasties. ].
Xi 1-8- 1
Guqinzi, which is similar in appearance, is different in plain face, bristles, melon edges and hexagon. Its quality can be said to be rich and colorful, including ivory, animal bones, horns, jade, crystal, hardwood, bamboo roots, copper and so on. The replacement and addition of restored guzheng should be considered comprehensively. The general principle is that guzheng with any shape and texture can also be used. If we consider the overall style of this piano, we should make some choices, or supplement it according to the original style and texture, or replace it with a guzheng that is more harmonious with the style of the piano. At present, ivory and crystal tweezers cannot be popularized, but other materials have a wide choice. I suggest using tweezers with melon edges or hexagons, which will help to adjust the strings and keep the hands smooth.
1-8-2, spike
At present, musicians use different ear lengths and colors, and sometimes they see red and white colors that are not suitable for individual use. According to research, the length and color of the ear of the clavichord are exquisite and reasonable. As the saying goes, "Taoism worships black, Buddhism worships turmeric, and talents are fragrant." . According to the characteristics of guqin, inspired by the different colors used by the ancients, I tried to use the principle of five elements (golden wood, fire, water and earth), five colors (yellow, white, red and black) and five tones (orthography in the upper corner of the palace) to make ears. Therefore, the colors of the seven strings of Guqin are "red, black, yellow, white, green, red (less sign) and black (less feather) from the outside to the inside. The piano body with elegant color and five-color tassels has considerable color, rich interest and deeper connotation. You can try it if you are interested.
Spikes are long, and you will often see some harps with short ears, short inches and a half, long feet and a half, or many tassels, which are ridiculed as rabbit-tailed squirrel tails. This is either too serpentine or not enough for a solid and beautiful piano body. Unfortunately, it can set off the ears of the piano body well, but it has no effect. What is the appropriate length and thickness? The author suggests that the ear length is one foot and one inch, which is the most harmonious and appropriate at the golden section of the height of the piano table. In addition, there is no need for tassels, the fineness is appropriate, and it is more quiet and simple, which complements the temperament of guqin. Because the length and thickness of tassels are appropriate, there is no stringed harp and wind tassels, the static harp is yin and the moving tassels are yang. One movement and one silence, one yin and one yang, make the piano move quite big and full of vitality.
Second, the repair example
1- 1 autumn morning, Mr. Cheng Gongliang's piano collection.
Qin Tang's "Qiu Lai" was collected by Mr. Cheng Gongliang, and the "Qiu Lai" was made by Li Jinxi in the third year of Kaiyuan in Zhong Ni style. It was painted in black paint, with spruce as the bottom, flowing water and small plum blossoms. From two holes in the pond, the wood was carbonized and turned purple. As the saying goes, "Tang is a round drum", but it is strange that the shoulder width is only 17.5cm, and the bottom plate is slightly concave inward. The effective chord length is111.3cm. The sound quality is quaint, quiet, gentle and round. The piano style is strong and steady, the lines are washed and practiced in the garden, and the style is rich and full, which is also great in Tang Zhiyun.
Symptoms: There are brake sounds in many places on the chord road, and the paint shell is loose at the local broken line. Check the thin layer of antler cream, the thickness is 0. 1-0.2 mm.
Repair process: check the Gao Diping inclination of its string, determine the increase or decrease, and try it while grinding at a high place. In the lower part, first use 80 mesh antler ash and raw lacquer (adding medicine) with black putty to supplement. Once dry, use 500 # water sandpaper to grind off the buds, then scrape the black putty with fine gray of 100 mesh repeatedly, with less water, and then use 600 # water sandpaper to grind it to a level, and gradually it will not reach. The loose part of the outer broken line of the string road is glued by injecting raw lacquer, pressed with bamboo and wood pieces and tied with ropes, and untied overnight. Use 600 # water sandpaper to gently polish the raw lacquer exposed in the crack on the dotted line, and wipe the repaired part clean again.
The restored piano has harmonious colors, pure sound quality and perfect overall effect, which better achieves the purpose of repairing the old as before.
2-2. Mr. Wu's Autumn
Mr. Wu's collection of "Qiu Jin" and "Qin" is a crescent-shaped dragon glue and a plastic bracket, which are hard miscellaneous wood accessories. The piano face is round and flat, with paulownia wood on the top and Chinese fir on the bottom. The wood in the observation cavity, the broken lines on the piano body and other factors broke it into Qin Song. After I repaired the stop, the piano was played by my teacher, Mr. Wu, for several months. The tone of the two-tone piano was better, but the overtones were unremarkable. After I removed the glue from the hardwood dragon, the overtone immediately became sensitive, the timbre was bright and clear, and the sound quality of the two-tone piano was quieter and more moist. This piano was invited by Mr. Wu to record a CD in Hong Kong, and its timbre effect is excellent. The background music "Fishing Song" and other songs often played in the "Poetry and Painting" column of Shanghai TV Station are played by Mr. Wu on the piano.
Discussion: There are many factors that restrict the piano sound quality. This is an example of improving sound quality by changing dragon glue. However, I don't think the piano is necessarily effective, because it has many kinds.
2-3, Qin Song He Ming, Chen Zang
Qin Song's "He Ming" is hidden by Mr. Chen. The "He Ming" piano is Zhong Ni-style, painted with black paint, with the upper tung and the lower catalpa, and the abdomen engraved with the words "Zhu Zhiyuan Rebuild" (Zhu Qin engraved the words "Made in Chicheng Zhu Zhiyuan", and this piano is "Zhu Zhiyuan", which is doubtful. )
Symptoms: First, Yueshan and Lu Cheng are loose; Second, there are many gaps around the piano; Third, the shell of the paint layer on the piano face and back is loose in many places. You can press the nail and break the paint layer with a little force. Repair process: re-glue the loose Yueshan dew with fish glue, and at the same time make a layer of hard wood chips on the inner surface of the dew, which is 0.3 mm lower than the forehead of the piano (it may be that the dew is lower than the forehead of the piano without considering the thickness of the paint layer). After gluing, the dew is 2.0 mm higher than the forehead, so there are ups and downs between the moon hill, dew and forehead. The gap around the piano was repaired with 80 mesh antler cream putty, and then with 100 mesh putty. After water milling, polishing and fading.
Where the paint layer is loose, puncture a tiny pinhole in the loose center with a sewing needle, dilute the raw paint (diluted with alcohol) with a medical needle, then inject it gently, remove the residual paint, press the loose place with a heavy object (the weight of half a brick), and it will dry overnight.
Discussion: The difficulty in repairing this piano is to prevent the paint layer from falling off during the repair process when repairing a large area of loose paint layer. Therefore, the method of reinforcing and repairing one by one was adopted, and four or five points were repaired at a time, each point was only one or two square centimeters. It took more than half a year to repair the paint layer of the whole piano shell.
2-4. Qin Song's Jin Sheng Yu Zhen is collected by the author.
Qin Song's Jin Sheng Yu Zhen is collected by the author. "Jin Shengyu Zhen" piano is Zhong Ni style, painted black and mixed yellow, and made of Tung Zi material. Carved on the abdomen of fengnuma. "eleven years of stagnation, Ai Wu laity rebuilt. Gold emblem, Hosta, this piano has complex broken lines, including a long-standing cow hair broken and a snake belly broken, as well as a dense lacquer broken and hidden broken.
Piano disease: the panel string road was hit by blunt objects in many places and braked. After I repaired the bruise, I wound up the wind and tried the sound. The scattered sound was acceptable, and the overtopping sound was dull. After the tenth emblem, there was a loud brake. I was too busy to repair the brake sound. Unexpectedly, after a few months, the brakes were all gone. Look at the body carefully. It is the tension of the seven strings that makes the tail of the piano flat.
Discussion: For a stringed piano that hasn't been played for a long time, there is no need to repair it in a hurry if the brakes sound the first time it is wound. The seven strings should be properly tightened, and it is better to discuss them in detail after the tension of the body is stable. This piano has been used by me for many years, and its sound has become moist, gentle and even.
2-5, Unknown Qin, with inscriptions (collected by Mr. Fu Huagen)
This piano was accidentally acquired by the owner in the woodshed of a friend's century-old house. Zhong Ni-style cedar wood surface, miscellaneous wood bottom, tile ash and antler ash, painted with black paint, and broken hair of cattle.
Qin disease: at the ninth and tenth emblems, the paint layer was damaged, and the depth was seen in wood. There were six or seven longitudinal cracks on the bottom plate (running through the bottom plate), with the length ranging from 10 to 20cm, and the bottom plate and guard plate were lost behind the pool. This piano was repaired by a piano friend first, and the damaged paint layer was filled with chemical glue. The cracks in the bottom plate are nailed to the panel to protect the geese from miscellaneous wood. If it is unpainted, the hands are made separately, and the nails are nailed under the piano head. If the dragon's chewing gum pillow is worn low, it is filled with bamboo chips. After the test, press one to seven strings and spread them evenly. When I repaired it, I removed all the mistakes, filled the damaged parts of the paint layer with antler ash, and rebuilt the Song horseshoe guard (palm) and mahogany goose web. Remove the nail from the bottom plate, blow off the dust in the gap with a dust blowing tool, inject hot fish glue into the arch part of the gap one by one, fix it with a clip and dry it. Then use 100 mesh antler cream putty to repair the paint. After the piano is repaired, the brake sound disappears, and the sound quality is quiet and soft, which is also a good piano.
Conclusion: People who have a good desire for maintenance and have no professional skills for maintenance had better not do it, otherwise it would be a pity to bend the piano.
2-6. Qin Ming's Gu Nan Yu Feng was collected by Mr. Wu Peng.
Qin Ming's "ancient style" is hidden by Mr. Wu Peng, and the "ancient style" is a black lacquered stringed piano. The panel is riddled with withered tung and the bottom is catalpa. The broken line of small running water is even and beautiful. The piano body is complete, and the phoenix tongue can move (rare). Antler ash is mixed with copper powder. The piano is extremely heavy, small in size, delicate and strange in tone, and has the sound of knocking on jade.
Piano disease: a broken protector. Due to the withered tung factor, the thin part of the panel has become a water leakage hole, mostly in the chord. Old pine is selected for filling the hole, depending on the size of the hole and the thickness of the plate. The difference is that it stops, the V-shaped rubber edge is used to repair the thick part, the rubber edge is used to repair the extremely thin part, and the bottom is connected. After wood restoration, primer, topcoat, polishing and other processes are carried out. Broken pieces should be copied according to the original type.
Discussion: "Ancient Jade South Wind" is quiet and far away, with only three deficiency and four excess diseases. This piano is caused by uneven thickness of the piano surface, which is very regrettable.
2-7, "Jiangshan romantic" Mr. Wu hides.
Jiangshan Yue Feng was collected by Mr. Wu. This piano was made by Zhang Yongshou, eunuch of Zheng Deyihai in Daming, and its timbre is quiet and long. Its Zhong Ni-style piano is flat and thin, with a flat Chinese fir floor, a big head and a small tail, an effective chord length of 1 16 cm, asymmetrical curves on both sides, irregular oblique holes in the pool, no bow thickness of Yueshan (1.2 cm) and an inclination of 0.8cm.. (One string is short and seven strings are long) The eye of the string is 0.9 cm away from the moon. It is difficult for a novice to master the intonation when playing this piano.
When repairing, depending on the thickness of the Moon Mountain, the first string is cut inside the Moon Mountain and the seventh string is cut outside the Moon Mountain. Finally, the Yueshan Mountain is cut into 0.4 cm thick, and the string is 90 degrees with Yueshan Mountain. Then pile the ashes of antlers in front of the string, one is to thicken Yueshan, the other is to let Yueshan close to the string eye, and then press Qin Hui. After the winding, the volume is not affected, so all three notes are straightened out.
Discussion: The production technology and sound quality of the handed down Qin are not all good, and many old musicians are even quite rough. However, this is not uncommon, and pianos eager to be widely used have good sound quality, such as the "Jiangshan Yue Feng" piano.
2-8, Mr. Qin's "Around the Beam".
Weng Shoucang hid the beams, and there was an ink book (illegible) in the piano cavity of the beams. It was learned that it was made in Kangxi period, with Zhong Ni style, wide and thick piano body, red bearded antlers, gray background and dull three tones, which was caused by the thick panel. Because the piano owner doesn't want to cut the piano and rebuild it, he only wants to repair the disease of the whole body brake string. Check the height of the dragon moon, the piano surface is flat and oblique, and the brake sound in a large area is caused by the large area of broken wires arching and disturbing the strings. When I repair, the braking area is controlled within the chord diameter (the broken line outside the chord diameter is reserved), and it can be completed by two or three fine grinding. There is no braking sound on the first to seventh strings.
Conclusion: The primer of this piano is coarse antler cream, so the broken line is long and arched. It is best to grind the brakes with a new oilstone soaked in water. Grind the arch, try less and try more, not too much. Never use water sandpaper to polish, because it is difficult to level with water sand.
2-9. The piano Lang Shiquan of the Republic of China was collected by Ms. Ye Mingpei.
The piano Lang Shiquan of the Republic of China was collected by Ms. Ye Mingpei, and the official collection Lang Shiquan was produced by the pianist Li Mingde of the Republic of China. The variant is beaded and densely covered with hidden broken lines. The piano body is wide and heavy, the panel is western pine, the ring of late wood is dark and shiny, and it contains more rosin. The bottom plate is three cross-spliced boards. (Crack) This kind of piano is weak, dull, and has a sense of retardation, and the vibration of the strings has no physical resonance. The first to seventh strings are all braked. After careful inspection, the foundation of the piano body is soft and I can't bear to follow the sound. In order to improve the sound quality of this piano, the old paint layer was removed from Huixian Road No.13 to No.4, and the antler cream primer was applied again. After the repair, the brake sound disappeared, the piano sound was opaque and the vibration was weak, which was greatly improved.
Discussion: Pine is solid and heavy. It seems that this kind of wood can't be used as vibrating material 13, and the piano is silent. Materials. This piano is really made of inappropriate materials.
Three. General introduction
1. The piano repairer should be a pianist, have good lacquerware skills, and have a certain level of understanding and artistic accomplishment in wood science, lacquerware science, acoustics, guqin aesthetics, etc.
2. Practitioners should start with the Qing Qin, and gradually master the experience before practicing the Qing Qin.
3. The restoration includes three contents: first, the appearance is harmonious and the style is consistent; Second, a solid internal structure; The third is to maintain, improve and improve the sound quality. Therefore, the restoration process of the piano should follow the tradition, and the materials used, such as fish glue, antler cream and raw lacquer, are pure and cannot be replaced by modern compounds.
4. In the late Qing Dynasty, due to historical and cultural reasons, its piano production technology should be said to be a declining period. It is rare to see good Qin, and many Qing Qin have been handed down, with low sound quality and many broken ones. In this regard, those who crack the glue will make up for it, and those who are damaged will make up for it. If the tile ash is badly damaged and cannot be pointed down, you can apply new ash (antler ash) on the old ash, and the sound quality may be improved. In a word, the Qin in the late Qing Dynasty, as a product of a specific period, is rare and can only be recorded in the history of Chinese guqin production.
5. Qin Ming in the Tang, Song, Yuan and Ming Dynasties was a treasure in guqin. Damaged ones should be repaired as soon as possible to prevent restorative damage. The principle is to keep more original works and repair old ones. If you add or subtract at will, the ancient meaning will be gone, and it is better to keep it as it is.
(End of full text)
This article was written in1April, 994, as an exchange paper of "International Appreciation Seminar of Chinese Guqin Masters and Music". 1994 was published in Chinese Musical Instrument magazine in September. This website is slightly revised and supplemented).