Chord progression

Chord Progression in Music Theory

A chord progression is a series of chords in music that play in a specific order, providing harmonic support for the melody and determining the structure, emotional atmosphere, and flow of the music. Chord progressions are a core element of many musical styles, playing a crucial role in both composition and performance, from classical music to pop, jazz, and contemporary music.

1. Definition of chord progression

A chord progression is the process of alternating chords in music. It describes the arrangement of a group of chords and their relationship to one another. Chord progressions support melodic development and build musical atmosphere, helping to create tension, release, and emotional intensity. Chord progression selection directly impacts the style and emotional expression of a piece.

2. The role of chord progressions

Chord progressions have many functions, the main ones being:

• Supporting melody : Chord progression is the basis of melody. It can provide a harmonic background for the melody, making the melody richer and more layered.
• Creating the structure of music : Chord progressions provide the framework for the structure of music. They divide the music into different sections or parts and help the music transition from one stage to another.
• Expressing emotions : Different chord progressions can create different emotional atmospheres. For example, a major key chord progression often brings a happy and cheerful feeling, while a minor key chord progression may express melancholy or sadness.
• Creating tension and release : Changes in chord progressions help create a sense of tension and resolution in the music. This process of tension and release makes the music more dynamic.

3. Basic concepts of chord progression

3.1 Functions of Chords

Chord progressions are usually built based on the function of chords. Chord functions can be divided into three main categories:

1. Tonic (I) : The tonic chord is the “home” or “foundation” chord in music, usually the first chord in the key. It gives a sense of stability and completion and serves as the final point in the chord progression. For example, in the key of C major, the C major triad (C) is the tonic chord.
2. Dominant (V) : A dominant chord is usually the fifth chord in a key, creating a strong sense of tension and requiring a resolution back to the tonic. A dominant chord is often constructed from a seventh chord, and its purpose is to lead the music back to the tonic. For example, in the key of C major, the G dominant seventh (G7) is the dominant chord.
3. Subdominant (IV) : A subdominant chord is the fourth chord in a key. It serves as a guide for the chord progression toward the dominant or tonic chord. It’s weaker than the dominant chord, but still possesses a certain tension. For example, in the key of C major, the F major triad (F) is a subdominant chord.

3.2 Common chord progression patterns

A chord progression is a series of chords arranged in a specific order. The most basic and common chord progression patterns include:

3.2.1 I-IV-VI process

This is the most common chord progression, widely used in pop music, blues, rock and roll, etc. Its structure is as follows:

• I (tonic chord) → IV (dominant chord) → V (dominant chord) → I (tonic chord) .
• For example, in the key of C major, the progression is: C → F → G → C.

This progression shows the stability and smooth structure of the music, and can create a sense of perfection. It is often used at the end of a song.

3.2.2 II-VI

This is the most representative chord progression in jazz music, but it’s also common in other genres. This progression is often used to create a sense of flow between chords. Its structure is as follows:

• ii (minor second chord) → V (dominant chord) → I (tonic chord) .
• For example, in the key of C major, the progression is: Dm7 → G7 → Cmaj7.

This progression often creates a strong sense of tension between the chords, which is then released onto the tonic chord, giving the music a sense of resolution.

3.2.3 vi-IV-IV

This is a chord progression commonly found in popular music, especially in modern pop songs. Its structure is as follows:

• vi (minor sixth chord) → IV (dominant chord) → I (tonic chord) → V (dominant chord) .
• For example, in the key of C major, the progression is: Am → F → C → G.

This chord progression creates emotional ups and downs and feels modern and lighthearted.

3.2.4 IV-vi-IV

This progression is the basis of many classic pop songs, including some of the most popular love songs. Its structure is as follows:

• I (tonic chord) → V (dominant chord) → vi (minor sixth chord) → IV (dominant chord) .
• For example, in the key of C major, the progression is: C → G → Am → F.

This progression is very melodic and creates an infectious emotion.

4. Changes and development of chord progressions

Chord progressions are not fixed; they can vary depending on the style and tempo of the music, as well as the composer’s creativity. Composers and arrangers often adjust chord progressions, for example:

• Chord inversion : The notes of a chord can be inverted (some notes in the chord can be raised or lowered) as needed, which can change the timbre and harmonic effect of the chord.
• Extended chords : Sometimes chords have extra notes added, such as seventh chords, ninth chords, eleventh chords, etc., which can create a richer harmonic effect.
• Modulation : The pattern of chord progression can ascend or descend, forming changes in chord progression, which can bring different musical colors and emotional fluctuations.

5. Application of chord progression in music

Chord progressions are used in different ways in different musical styles:

• Classical music : Chord progressions in classical music often follow strict harmonic rules, focusing on the balance and stability between chords.
• Jazz music : The chord progression in jazz music is more improvisational, often using complex chords such as seventh chords and ninth chords, and the chord progression changes are relatively free.
• Pop music : The chord progression in pop music is relatively simple, with I-IV-V progression being the most common, and it focuses on the combination of melody and chords.
• Blues Music : The chord progression in blues music usually uses a 12-bar blues progression, emphasizing the V-IV-I progression.

6. Conclusion

Chord progressions are crucial elements in music composition. They not only underpin the melody but also influence the music’s emotional expression, structural variations, and stylistic characteristics. Different chord progressions can create varying atmospheres and tensions, adding depth and dynamics to the music. Understanding and mastering the fundamental principles and patterns of chord progressions can help composers, arrangers, and performers create more compelling and profound music.

Note: This article was originally written and edited by AI. Editor: Wu Lecheng, Managing Editor: Eric Lok