The concept of interval is as follows:
Interval refers to the relationship between two tones in pitch, that is, the distance between two tones in pitch, and its unit name is called degree. Degree, as the unit of interval, is the quantitative unit of the difference between two notes by several natural sound names. For example, four degrees refers to four natural sound names counted from this sound.
For example, the degree algorithm between DO and FA is four natural sound names: DO, RE, MI and FA, so the degree between DO and FA is four degrees. Pure fourth degree: a fourth degree containing two full tones and one semitone, that is, a distance of five semitones, is a pure fourth degree. For example: c–f; D–G。 The size of an interval is measured in degrees.
The attribute of each interval should be determined by two conditions: first, the number of tones contained in the interval; Second, the number of semitones contained in the interval. It doesn't matter if this interval is big, small and complete. But if it is not, an interval that is more than a major interval or a complete interval is called an interval.
conversely, an interval that is half a tone less than a minor interval or a complete interval is called an interval reduction. Music theory, referred to as "music theory" for short, includes relatively simple basic theory reading spectrum, interval, chord, rhythm, beat and so on. There are relatively advanced harmony, polyphony, form, melody, orchestration and so on.
Mastering music theory is of great positive significance for composing, arranging, conducting and playing. What we usually call music theory generally refers to the basic part of music theory, that is, "basic music theory". There are numerous works about basic music theory, among which the most popular one is The Basis of Music Theory compiled by Li Zhongguang of the Central Conservatory of Music.
degrees can't show the exact distance between DO and FA, and the exact distance should be calculated by semitone. Because if we only use degrees to calculate intervals, there will be a problem: although some degrees are all called four degrees, the number of semitones between them is different, for example, there is a difference of five semitones between DO and FA, and six semitones between FA and SI. The degrees are the same, but the actual distance is different.
Therefore, after determining the degree of this group of sounds, adjectives such as big, small, increasing and decreasing should be added in front of the degree to further determine the correct interval of this group of sounds. The lowest degree between homophones is called one degree, and those separated by one tone are called two degrees, and so on.