According to legend, the six strings and seven strings of the guqin were made by Zhou Wenwang and Zhou Wuwang respectively, but the shape of the seven strings of the guqin was stable in the middle of the Warring States Period, so it is said that the guqin is not five tones but seven tones (not strictly speaking).
From the late Han Dynasty and the Three Kingdoms to the Wei and Jin Dynasties, the subtraction spectrum of guqin was basically formed, and it has been used ever since, but the early piano spectrum had a whole-word spectrum (I wrote the fingering in detail myself, so I gave myself a name without abbreviations).
Theoretically speaking, there is no "five tones" and "ancient music". Since the mid-Warring States period, the shape of guqin has stabilized to seven strings, which is the so-called "seven tones"
However, there are still some ancient piano works. As usual, six-string and seven-string are rarely used. It is generally believed that this piece of music was written earlier.
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