don't call me singer

Chapter 39 The physics tyrant actually did this kind of thing to the musical instrument

Then, Zhao Xingsheng saw that Gu Xiaobai was using his mobile phone to check information, while writing calculations on paper.

Dizi, or Chinese flute, bamboo flute, is divided into "bang flute" and "qudi", the two are northern flute and southern flute respectively. High-pitched, mainly tongue skills; southern flutes are thicker and longer, with a mellow sound, which matches the southern Kunqu district, which is tactful and soft, and mainly finger skills.

In fact, there is no strict difference between the two, but the tone is different. In terms of structure, they all include the body of the flute, the flute plug, the blow hole, the membrane hole, 6 finger holes, the fundamental sound hole, the auxiliary sound hole and the flute plug. Some There are also metal connectors for fine-tuning the tone.In addition, there are decorative silk wraps, floating ears, inlays and so on.

If you want to make a flute, you can't just drill these holes in the bamboo. It's not easy to make every sound accurate.

Zhao Xingsheng himself does not know how to make flutes, but he has seen the operation of some flute masters in his early years.

First, make a blow hole on a piece of flute material, usually a bitter bamboo or "three-year-purple" purple bamboo, and then plug a flute plug on one side to block one end, so that the airflow is only transmitted to the other side.

Then open the base sound hole.Start by drilling a small hole first, and blow it while expanding it. Is the earpiece sound correct? If the sound of the earpiece is low, open the hole a little bigger to the side of the blowing hole, and open it to the other side when it is high, and just drill out the base sound hole .

Then continue to drill the finger holes...

Drill one by one, try one by one, if you are not careful, a good flute material will be scrapped, which is embarrassing.

In fact, if you don't have many years of experience, you may not even know where to open the first blow hole.

Therefore, many bamboo flutes must be written by famous masters to prove their intonation and noble status.

Just like that, Gu Xiaobai actually wanted to make a flute by himself?

This kid doesn't know how easy this is to say and how hard it is to do, right?

Then he heard Gu Xiaobai muttering softly: "Well, this is the problem of vibration caused by the turbulent flow of a cylinder under a circular section..."

While talking, he opened HowNet.

It was the first time that Zhao Xingsheng made a flute while checking papers!
He widened his eyes and approached Gu Xiaobai curiously.

Then he heard Gu Xiaobai muttering:
"Let the inner diameter of the flute be D and the length be L."

"Open the blow hole first, L0 is the distance from the gene hole to the blow hole, L1 is the distance from the first finger hole to the blow hole, and L2 is... The distance from the blow air to the membrane hole is Lm..."

"The ratio between inner diameter D and L0 is about 20."

"The relationship between the distance Li (i=0, 1, 2,..., 6) between the blow hole and the finger hole and the pronunciation frequency fi (i=0, 1, 2..., 6) follows the formula Li=v/ 2fi-ΔL (i=0, 1, 2, ..., 6) is calculated.

"Where V is the speed of sound, and the speed of sound is related to temperature. Taking an average value of 25 degrees, the speed of sound is 345700mm/s."

Seeing Zhao Xingsheng looking at him, Gu Xiaobai raised his head and explained:
"The relationship between the resonance frequency f of the open tube at both ends and the length l is Li=v/2f, but the vibration of the cylinder and the vibration of the string are different, so there is a problem of edge air vibration, so a correction compensation length is added. ΔL, according to the research data, this ΔL=4D (mm) is more suitable..."

Zhao Xingsheng shook his head and said, you don't need to explain it to me!
I don't want to hear it at all!

Can't even hear it!
I don't know how to use it!
Use it will not say!
I just want to give my knees to survive like this!
He already roughly understood why Gu Xiaobai could read an introductory book on music theory so quickly... For a physicist, the interval conversion in music theory, the circle of fifths, etc., are simply too childish, right?

"Okay, it's done."

Then he saw Gu Xiaobai write down a very short formula on the paper, and then redraw it with a pen.

"Okay, just find a piece of bamboo, and then substitute its inner diameter, you can calculate the distance from each hole to the blow hole, and then just punch the hole directly."

Zhao Xingsheng was dumbfounded.

"Is this the end?"

"It's over."

"What kind of flute can this tune?"

"From A to G, you want a flute in whatever tune you want, or even a flute that's not tuned. You can make whatever frequency you want." Gu Xiaobai pinched it. Chin, two eyes sparkling.

His eyes are so bright only when it comes to physics.

Even brighter than when singing on stage.

Zhao Xingsheng picked up the white paper in front of Gu Xiaobai.

It is not a long formula, and the verification process is from start to finish, no more than 20 lines.

Simple, straightforward and clear, there is a strange beauty.

But this formula is enough to make countless craftsmen pursue it for a lifetime but never get it.

He only felt that if the master flute maker who had been immersed all his life, saw this formula of Gu Xiaobai, he would definitely fall to the ground and never want to get up again.

Who can tell me why a music problem has become such a simple formula in the blink of an eye.

As a historian, he also knew that physics could solve many problems.

But... when this kind of thing really appeared in front of him.

"Fortunately, I'm a liberal arts student! I don't have to live with this pervert."

He is very happy, very happy!
Gu Xiaobai can't wait to test whether his data is correct, just like every physicist who has completed the theory can't wait for someone to confirm himself with experiments.

"Teacher..." He asked, "Do you think that if I go to the school's bamboo garden and steal a piece of bamboo, will my uncle police arrest me?"

"Yes." Zhao Xingsheng wanted to touch Gu Xiaobai's head. Is this child stupid?
"Then, teacher, can you help me let loose?"

"What the hell are you thinking!" Zhao Xingsheng really exclaimed, "It's getting late, go back to sleep!"

"Well...then I'll go and steal it tomorrow morning..." Gu Xiaobai refused to give up his criminal plan at all, "Teacher, if I'm caught by the police uncle, can you lead me out?"

Gu Xiaobai looked at Zhao Xingsheng as if it was all up to you.

"I..." Zhao Xingsheng wanted to refuse, wanted to say no.

How can I support you to commit crimes!Xiaobai, you are the hope of the whole school, and you are the candidate of the school hundred sons!
"I'm going to steal bamboo early tomorrow morning. Teacher, you must turn on your mobile phone in the morning!"

Gu Xiaobai said.

Zhao Xingsheng felt that it was over. For such a good seedling, for a bamboo flute, he would embark on the road of crime from now on. He was imprisoned and hated for the rest of his life...

Xiaobai, Xiaobai, for the sake of physics, you are not worth it, you are not worth it!
Gu Xiaobai's impatient look shocked the system.

Is this still the Gu Xiaobai who has no interest in music and even wants to give up?
Sure enough, Gu Xiaobai has fallen in love with music!
Great, I won't be kicked out of the house!
But...why did this change happen?

Is it the charm of crime? !

The system felt that it should support Gu Xiaobai's crime.

"Additional teaching task: making a bamboo flute. Successfully making a bamboo flute will reward the passive training of primary bamboo flute playing skills."

Note 1: At present, there are only some sound hole size comparison tables on the Internet. Look at the instructions, and you still need to fine-tune it when you actually make a flute.

Note 2: The formula comes from Professor Wu Jike, a retired physics professor and doctoral supervisor at Peking University, and pays tribute to the elderly.

Note 3: The actual situation of the musical instrument is much more complicated than the formula, especially the control of pitch and timbre, but Uncle Ha is not writing a paper~ That's it, perfect!
(End of this chapter)