The pentatonic scale in China ancient music refers to

The five tones of chimes are also called "five tones". It refers to the five tones of China's pentatonic scale: Gong, Shang, Jiao, Zheng and Yu. The interval between two adjacent notes in pentatonic scale is two degrees [1], except that the interval between the horn and the sign, the feather and the palace (the house with an octave higher) is three degrees. As Guan Yuan said: "When listening to a feather (yoh) like a horse in the wild, when listening to a palace (kiung) like a cow in the nest, when listening to a merchant (sjang) like a lost sheep, when listening to a corner (kruk) like a pheasant climbing a tree, the sound is clear." Five sounds are equivalent to 1, 2, 3, 5, 6 in the current notation. After the Tang Dynasty, it was called He, Si, B, Chi and Gong. In phonology, five syllables refer to five pronunciation parts of five initials, namely throat sound, tooth sound, tongue sound, tooth sound and lip sound [2]. Shen Kuo's "Meng Qian Bi Tan" said: "The lips, teeth, tongue and throat of a rhyming artist are all feathers on the corner of the palace." According to the records in Qi Yin Lu and Yun Jing Fan Fan, there is a corresponding relationship between the feathers on the upper corner of the palace and the 36 letters of the initials in medieval Chinese: Xiao Yin [h] box after the palace [? 0? 4] Shadow [? See [k] Xi [kh] group [g] doubt [? 0? 7] Tongue sounds [t] penetrate [th] and settle in [d] mud [n] Shang Ya Yin Jing [ts] Qing [tsh] from [dz] heart [s] evil [z] feather lip sound gang [p] and [b] name [m] wrong. 0? 8] Half-symbol and half-tongue sounds come [l] Half-quotient and half-tooth sounds day [? 0? 2? 0? 9]