Seek the basic knowledge about music theory and seek the details.

I'll just copy some basic contents I wrote to you. If you still don't understand, add me For contact information, see User Name. Let's talk about some conceptual things first. Music theory, as its name implies, is the abbreviation of music theory knowledge. What's that music? It refers to an art that combines organized and orderly music sounds to express people's thoughts and feelings and reflect real life. This is called music. The emergence of musical sound system: sound is a physical phenomenon. When an object vibrates, it will produce sound waves, which will pass through the air to people's hearing organs and be perceived as sound after being reflected by the brain. In nature, there are many kinds of sounds, some we can hear and some we can't hear. The sound that our human ears can hear is within the range of vibration per second (1 1-20000), while the sound used in music is generally within the range of vibration per second (27-4 100). Nature of sound: According to the physical properties of sound, it has four properties: height, length, strength and timbre. The four attributes of sound are of great significance in music expression. Due to the difference of sound level, length and strength, different melodies can be obtained, and the timbres produced by various musical instruments can be distinguished according to different timbres. As usual, if someone calls us outside, we will know who it is, because the timbre is different. The sound level depends on the number of times (frequency) that an object vibrates in a certain period of time. The more vibrations, the higher the sound and the lower the sound. The intensity of sound depends on the amplitude of the object. The greater the vibration amplitude, the stronger and smaller the sound. The length of sound depends on its duration. The longer the duration, the longer and shorter the sound. The timbre of the sound depends on the nature and shape of the pronunciation body itself. Classification of sound: According to the regularity of object vibration, sound is divided into noise and music. The sound produced by the regular vibration of an object is called musical sound, and its level sounds very obvious. The sounds made by piano, guitar, flute and other musical instruments are music. The object vibrates irregularly and the sound level is not obvious. It's called noise like a drum, and the sound made by wooden fish belongs to noise. Music is mainly used in music, but the use of noise is also essential, such as the use of drums in music, which is irreplaceable by musical instruments. If there is no drum, it feels like a tree without a main pole. It shapes the image of music and has strong expressive force. The sum of the basic musical tones used in music is called the musical tone system. Every tone in the music system is called a scale. In the musical system, sounds are arranged in a certain pitch relationship and high and low order, which is called sequence. In the music system, the distance between sounds, that is, the pitch relationship, is called interval and expressed by the unit "degree". The smallest unit is a semitone, and the sum of two semitones is a whole tone. Details will be mentioned during the intermission. On a piano keyboard, including black keys, two adjacent keys are semitones. Two keys separated by a key form a whole tone. The bass is on the left and the treble is on the right. The 88 different notes of the piano include almost all the notes in the musical system. Otherwise, how can it be called "the king of musical instruments"? Sound name roll call: 1234567. We pronounce it DO RE MI FA SO LA XI, so it is also called roll call. And their sound names are: C D E F G A B in turn. Except that E-F and B-C are semitones, that is, two degrees, all adjacent sounds are full tones, that is, two degrees. There are also basic knowledge such as tone group, twelve-average law, equal tone, polyphonic overtone, range and range. We quote rhythm, beat: beat refers to a time period with the same strength, which is repeated in a certain order and is called beat. Rhythm is simply the relationship between the length of sound organized by strength and weakness. In musical works, the typical rhythm is called rhythm type. Rhythm and beat are important parts of music creation, which is of great significance. Rhythm and beat coexist forever in music. Music is composed of the length, intensity, fixity and accuracy of sound. Rhythm and beat are the soul of music. Without rhythm, the band can't play perfect music. Drums, guitars, bass and vocals can't keep up with the same rhythm in time, which is almost out of order. Each time period in a beat is called a unit beat, which is also a beat. The first unit beat with strong sound is called strong beat, the other unit beats with strong sound are called secondary strong beat, and those without strong sound are called weak beat. Editor: CC writes down his own experience and communicates with each other if there are shortcomings! ! ! A work consists of music, lyrics and accompaniment. Chords are the most important part of adapting a piece of music. Since you are composing chords, you must first know what chords are. The relationship between pitches of more than three tones (including three tones) is called chord. Although this is the definition of chord, the definition of chord in modern music seems to have changed. Just like playing the piano, we press several notes at the same time. Maybe we don't know what chord it is called, but we know its constituent sounds. As long as you listen to harmony and suit the musical artistic conception you want to express, it is chord. Composition of chords: A. Trichord: A chord composed of three tones in a three-dimensional relationship is called a triad. Common triple types are: 1. Major triad: The root of the third note is a major third, the third to fifth notes are a minor third, and the root of the fifth note is a pure fifth. (The distance between sounds is called interval, which is expressed in degrees. ) 2. Minor chords: the root to the third tone is a minor, the third to the fifth tone is a major third, and the root to the fifth tone is a pure fifth. Unusual triple types are: 1. Add a triad: the root sound to the third sound, the third sound to the fifth sound are all major triad, the root sound to the fifth sound is increased by five degrees, and the added triad has the characteristics of outward expansion. 2. Subtract triad: The roots of the third and fifth notes are minor, and the roots of the fifth note are all minus five. Subtraction triad is characterized by inward contraction. Summary: Major chords and minor chords are both harmonic chords, because the intervals they contain are all harmonic intervals (major third, minor third, pure fifth). The increase and decrease triads are dissonance chords, because the increase and decrease of the five degrees they contain are dissonance intervals. B, seventh chord: A chord in which four tones are stacked in a three-degree relationship is called a seventh chord. Seven chords can be divided into many chord forms with different properties. Let me give you an example here. Let's take key C as an example: common chords in key C: C, Dm, Em, F, G, AM (I, II, III, IV, V, VI chord series). The first level is the main chord, the fourth level is the subordinate chord and the fifth level is the main chord. Before you start composing chords, you must know which sounds each chord is made of, as well as their interval relationship and different colors. C: do mi so (135) DM: re fa la (246) em: mi so si (357) f: fa la do (461) g: so si re (572) am: la do mi (613). Major triad has (c, f, g). The timbre of minor chords is dim and depressing. Just like rainy weather gives people a slightly sad charm. But it is also stable and harmonious. The minor chords are (Dm, Em, Am). Music in a big mode is generally cheerful and bright. The ending sound of a phrase is usually on the DO sound. (Like BEYOND's Really Love You and Jay's Li Qixiang) And minor music is generally sad and dim (such as Vae's Broken Bridge and Half the City's Smoke and Sand). The ending sound of a phrase is usually on the LA sound. Of course, there are some music exceptions, and its ending sound is mi sound, or other sounds. In any case, it is to better present the artistic conception, emotion and musical color expressed by this piece. Application of chords at all levels: C chord: I chord, used to clarify tonality. Generally, songs in major begin and end with it, giving people a perfect sense of termination. Dm chord: The second chord is a very soft chord, which is intended to be placed before the dominant chord. Em chord: The third chord is also a very soft chord with a slightly sad charm. F chord: ⅳ chord, which is subordinate chord and belongs to one of the backbone chords. Like the c chord, it is very bright and open. G chord: ⅴ chord, which belongs to a chord, is self-evident in importance and plays a role in supporting the main chord. Generally speaking, music ends when it reaches the main chord. (g-c) AM chord: chord of grade ⅵ is neutral chord. If it is the main chord, it is a minor, and the song must be sad. Now that we know the constituent sounds and colors of each chord, it is not a problem to arrange the chords. See the picture "I really love you" or use this song as an example. Ha ha! ! ! This song is in C major, and it must undoubtedly start and end with a C chord. There is a simple and practical method, which sound appears most frequently in a bar, and then choose which chord to use according to the composition sound and color of each chord. C-G is played at the fifth degree, and playing at the fourth or fifth degree is the most stable in music, so that you can get flowing sound effects and give people a very comfortable feeling. Subordinate chords can go directly to the dominant chord (F-G), which is generally used to enter the climax of the music because it has great propulsion. See the picture, I really love you is like this. Including a lot of music, all here. Playing with musical instruments can tell whether the chords are harmonious, whether the chords are played properly and whether the sound effect is perfect. Slowly, I will sum up some experiences and skills. The chord direction of each piece of music is regular, because the composer composes according to a certain harmony direction, otherwise it is really impossible to arrange music. Like many modern music, the progress is similar, such as Who will you think of when you are lonely, Absolute infatuation and It's hard to love someone. Music, that is, those seven notes, can't be used without certain rules. As long as you practice more, practice makes perfect, and chord arrangement is very easy.