A flute enthusiast said that a computer expert who was familiar with lathes wanted to use a computer (programming) to control the lathe to make flutes. The computer expert believes that as long as there is reliable data, a series of process operations such as opening holes and scribing will be more precise than manual production when making flutes. The computer expert also believes that if this method can be successful and applied for a patent, it should have application value. In addition, I heard that more performers and researchers of flute making technology have jointly conducted this research.
It is not difficult to apply for a patent. The reason is that patents only require "new". For example, in the 1930s, Zhang Xielin designed an eleven-hole flute. In recent years, someone added two supports to it. Not only did he apply for a patent, but he also won the "Third Prize for Scientific Progress" from the Ministry of Culture; another example is that someone made The glass imitation jade flute has also been recognized by experts and has also been patented; for another example, the alto wind instrument made according to the folk instrument "chi" - or the so-called "Jiahu Bone Flute" has also been patented. Got a patent? Aren't these patents obtained because of "newness"?
In the 1930s, there were no patents in China. Of course, Zhang Xielin could not apply for a patent for the eleven-hole flute, and now the patent office has no way of inspecting it. "Double-supported eleven-hole flute" is just a double-supported eleven-hole flute. I once asked the jury for advice, and the answer was "No one plays the eleven-hole flute, so where can he play it now!" I know that the player spent eight years and now he can play Rimsky-Korsakov's "Wild Flute". Bees dance like crazy". Eight years - difficult but not valuable: professional performers don't have this patience, let alone amateur performers? The strange thing is that the "Double Support Eleven Hole Flute" won the "Scientific Progress Award", not the Performance Award!
Back to business, let’s talk about the issue of standardized research on computers and musical instrument production.
If computers are used to develop flute making software, is it possible to conduct standardized research on flute making? The author believes that under special conditions, it is feasible; but under general circumstances, it is not feasible!
So under what circumstances can computers be used for standardized flute production, and under what circumstances cannot computers be used for standardized flute production? I think that elephant flutes can be made with a computer setting program; if Chinese flutes are turned from metal, hardwood or plastic, it will be difficult to make with a computer setting program; and as for traditional bamboo flutes, they can be made with a computer setting program. It’s simply impossible to make! Because using computer settings to make flutes of new materials is by no means just a matter for the producer, it also involves the basis for obtaining data, the scientific nature of teaching materials, and the coordination of teaching, musical instrument production, and teaching materials; as for bamboo flutes, That is completely a luxury!
Why can a flute be made using a computer setting program, but it is difficult to make a flute made of new materials using a computer setting program, but it is impossible to make a bamboo flute? This is determined by their respective characteristics. Although flutes made of new materials (metal, wood, plastic) can be turned from the same materials as flutes, on the surface there is not much difference, but in fact they are quite different. It's not difficult to figure this out, just know the difference between them. There are two important differences between Chinese flutes and flutes: first, there are many schools of Chinese flutes, and second, there are no unified teaching materials and teaching methods. These two issues are actually related to each other: the existence of schools makes it impossible to unify teaching materials; the non-unification of teaching materials is the basis for the inheritance and development of schools.
The most important attributes of an instrument are timbre and pitch: a unique timbre is the foundation of its life; good pitch is the condition for its application. The unique timbre of the bamboo flute makes it impossible to replace it with a more advanced flute. If the production cannot guarantee the pitch, then it can only remain among the people and cannot enter the hall of concerts. This shows the importance of timbre and pitch.
The pitch of the flute is not only determined by production, but also by teaching. Flute production has strict technological requirements. These requirements are the continuous summary and sublimation of hundreds of years of production experience, not the deduction of mathematical formulas. The flute playing teaching materials are adapted to the intonation conditions of the flute and are supplemented by strict sight-singing and ear training to ensure it.
Our country's flutes lack this prerequisite. The strictness of the computer application can only meet the playing conditions of some people, but cannot meet the playing conditions of all players. As for the bamboo flute, the materials are ever-changing, so how can it be made with the same specifications and meet the pitch requirements?
The indisputable fact about the production of ancient and modern flutes is that they have always been made based on experience rather than strict calculations. From ancient times to the present, there are only two pieces that stipulate clear sound hole positions and intonation requirements based on calculations: one is the flute rhythm formulated by Xun Xu, the eunuch in the 10th year of Taishi in the Western Jin Dynasty (i.e., "Xun Xu Flute Rhythm"). According to Xun Xu's The "Taishi Flute" made by the Dilu Company; the other one is the "Ya Xiao" (Qin Xiao) designed by Peng Zhiqing of the Jinyu Qin Society in the 1930s. Among these two instruments, the intonation of the Taishi flute conforms to the three-point law of gain and loss and the twelve-tone law. The pitch requirement of the Yaxiao not only conforms to the three-quarter law of gain and loss, but also uses a1 as the standard tone. However, these two examples do not prove that the strict laws of flute and flute can be found through calculation, because when opening the data obtained through the "formula", flexible methods must be fully used to ensure the pitch; otherwise, the accuracy of the pitch can be guaranteed. The sound is impossible to get right. For example, the author has been exposed to the "uniform hole flute" for more than 50 years, and the production of the uniform hole flute has been around for 46 years. However, in the past ten years, through the specific application of nozzle correction theory, the same production formula has achieved strange effects: its modulation effect is beyond the reach of predecessors.
As for the frequency formula for making flutes, Mr. Zhao Songting once developed the "Flute Frequency Calculation Formula" with his brother, Mr. Zhao Songlin, a professor of the Department of Physics at Fudan University. Many people have mentioned this formula to me. I think that although this formula considers the factors that affect the frequency of the bamboo flute more thoughtfully than its predecessors, it is still a formula that needs to be further improved before it can be put into practical application. Many people are skeptical about the formula summarized by Mr. Zhao. The author has no intention of commenting on the formula itself, but the results calculated by Mr. Zhao based on the formula cannot conform to the actual production of flutes, so it can be concluded that the formula is imperfect. In fact, Mr. Zhao himself understands the imperfection of the formula, and his answer to the author's question reflects this attitude. The reason why Mr. Zhao didn't perfect it was not because he didn't do it, but because he couldn't!
The following is intended to discuss Mr. Zhao’s flute frequency calculation formula.
Mr. Zhao’s formula is incomplete, so the calculated flute production data cannot be put into production. This is proved by the distance between the second and third holes. The distance between the second and third holes of the flute in D is 0.25 cm, the distance between the second and third holes in minor A is 0.1 cm, and the distance between the second and third holes in minor C is only 0.06 cm! Just imagine, even if bamboo fiber can have such high mechanical strength without breaking, I am afraid that the gap between the index finger and middle finger will be much larger than this figure and cannot be pressed①.
The reason for this mistake is not only that Mr. Zhao failed to pay attention to the fact that the distance between two adjacent holes (that is, the distance between the center points of two adjacent holes) should be minus the radius of the two adjacent holes. For example, for a D-tuned flute, the distance from the blowing hole to the second hole is 24.41 cm, and the distance to the third hole is 23.16 cm. It seems that the distance between the two holes is 1.25 cm; but the radius of the two sound holes (0.5 ×2), only 0.25 cm is left! Of course, if one is made based on the calculated data, wouldn’t the problem be discovered? But Mr. Zhao has never made one according to the data he calculated.
As far as the frequency formula for flute production calculated by Mr. Zhao is concerned, I think that two of the physical quantities selected may not be appropriate: one is the sound wave speed, and the other is the nozzle correction quantity.
Everyone knows that frequency is directly proportional to the speed of sound waves. Therefore, the speed of sound waves determines the frequency. The speed of sound in the formula is the speed in free space (atmosphere); the inner diameter of the flute tube is generally relatively small, not exceeding 2.5 centimeters, and the speed of sound in the tube should not be equal to that in free space. Whether they are equal or not is a question that remains to be verified.
The second is the nozzle correction amount. There are two correction amounts for the mouth of the flute, one is the end correction amount and the other is the end correction amount.
The end correction amount selected by Mr. Zhao is 0.6R, and the pipe end correction amount is a variable. Regarding this terminal correction quantity, it is the 0.6R measured by the acoustician Rayleigh. I once wrote an article "Rayleigh's terminal correction is difficult to apply to Chinese flutes"② and raised objections to the quantity chosen by Mr. Zhao. As for the pipe end correction quantity, although Mr. Zhao paid attention to the influence of blow hole size and tube wall thickness on frequency, it was not appropriate for him to regard this quantity as a constant. Why, even if a well-made flute is made, not everyone can play it accurately. What's the reason? This phenomenon just proves that the pipe end correction amount is a variable, not a constant.
Two factors that affect the pitch of the flute are the sound wave speed and the correction amount of the pipe mouth. How do we distinguish the effect of sound speed on flute pitch and the effect of nozzle correction on flute pitch? In fact, it is not difficult to distinguish: if the overall pitch of the flute changes, but the intervals between the sound holes do not change, it proves that the speed of sound affects the pitch of the flute. For example, the absolute pitch of the same flute in winter and summer If the pitch is different, the interval will not change; if the pitch of the flute changes, the intervals between the sound holes also change, which proves that the correction amount of the mouthpiece has an impact on the pitch of the flute. .
The influence of sound wave speed and pipe orifice correction on flute pitch is not difficult to prove through formulas. The following is a brief analysis.
It can be seen from the basic formula of flute F=C/2(L Δ) that when the tube length L remains unchanged and the tube mouth correction amount Δ remains unchanged, the frequency F is proportional to the sound wave speed. Therefore, the speed of sound only affects the overall pitch of the flute. Without changing the interval relationship between each sound hole.
The above formula can also be used to derive the phoneme formula of the flute.
Since when a certain flute is played at a certain temperature, its sound wave speed is certain, therefore, f1/fn=(Ln Δ)/(L1 Δ). If the rhythm system (method of generating rhythm) is selected as k, then fn=kf1. Since the frequency of fn is greater than f1, k is greater than 1. At the same time, the above formula can be derived from the following formula Ln Δ=k(L1 Δ); Ln=k(L1 Δ)-Δ; Ln=kL1-(1-k)Δ;
Due to the frequency It is inversely proportional to the tube length, so k is less than 1 and greater than 0; (1-k) is a constant less than 1 and greater than 0. The sound hole position Ln rises and falls with the increase or decrease of the tube mouth correction amount Δ.
As mentioned before, Δ is the sum of the end correction amount amp; 1 and the pipe end correction amount amp; 2. Not only can the end correction amount not be 0.6R, but it is still a variable: this amount decreases as the tuning hole at the end increases, and increases as the diameter difference between the two ends increases. As for the pipe end correction amount, it not only decreases with the increase of the blow hole, but also increases with the thickening of the pipe wall; it also increases with the forward movement of the mouth seam position and decreases with the increase of the mouth wind intensity. In addition, the pitch of each sound hole also rises and falls as the diameter of the sound hole increases or decreases. Every flute maker (whether you do it consciously or unconsciously) uses these relationships to adjust pitch.
These conditions that affect the intonation of the flute are flexible and changeable. I am afraid that no one can grasp their changing rules now. People haven't figured out the rules yet, so how can we dictate that computers be made according to certain programs?
It can be seen that today’s research on making flutes using computers will be futile and waste manpower, material and financial resources. Only after we have mastered the frequency formula and phoneme formula of the flute described above, that is, after we have mastered the relationship between the frequency of the flute and the above-mentioned quantities, can we put computer programming on the agenda and be successful.