An In-Depth Exploration of Chords: Triads and Seventh Chords

Music, a universal language, is fundamentally built on harmony and melody. Chords, which form the backbone of harmonic progressions, can evoke emotions, create tension, and provide resolution within a piece. This essay delves into the various types of chords, focusing on triads and seventh chords, providing background information and examples to elucidate their roles in music theory and practice.

Triads - 3 Note Chords

Triads are the simplest form of chords, consisting of three notes: the root, third, and fifth. These foundational structures are pivotal in Western music, serving as the building blocks for more complex harmonies. By combining different intervals between these three notes, triads can evoke a wide range of emotions and atmospheres, from stability and brightness to tension and darkness. Understanding the various types of triads is essential for any musician or composer aiming to grasp the basics of harmonic theory. There are 4 basic triad types: Major, Minor, Diminished, and Augmented. There are also “suspended” chords, which are similar to a triad.

Major Triads - Bright Sounds

Major triads are composed of a root note, a major third, and a perfect fifth. They are characterized by their bright, happy, and stable sound. The interval of a major third (four semitones) above the root and a perfect fifth (seven semitones) from the root creates a consonant and uplifting chord. Major triads are ubiquitous in Western music, forming the harmonic foundation of many classical, pop, and folk songs. An example of a major triad is the C major triad, consisting of the notes C, E, and G.

1. Major Triads

   - Construction: Root, major third (4 semitones above the root), perfect fifth (7 semitones above the root).

   - Sound: Bright, happy, and stable.

   - Example: C major triad (C - E - G).

Minor Triads - Dark Sounds

Minor triads consist of a root note, a minor third, and a perfect fifth. They have a melancholic, sad, and sometimes introspective quality. The minor third (three semitones) interval gives minor triads their distinctive sound, contrasting with the major triad's brightness. Despite their somber tone, minor triads are equally important in music, often used to convey deeper emotional content. An example of a minor triad is the A minor triad, which includes the notes A, C, and E.

2. Minor Triads

   - Construction: Root, minor third (3 semitones above the root), perfect fifth.

   - Sound: Sad, melancholic, and somewhat stable.

   - Example: A minor triad (A - C - E).

Diminished Triads - Tense Sounds

Diminished triads are built from a root note, a minor third, and a diminished fifth. These chords are known for their tense, unstable, and dissonant sound. The diminished fifth (six semitones) interval introduces a level of dissonance that makes diminished triads useful for creating tension and anticipation in music. They are often used in classical and jazz compositions to lead into more stable chords. An example of a diminished triad is the B diminished triad, comprising the notes B, D, and F.

3. Diminished Triads

   - Construction: Root, minor third, diminished fifth (6 semitones above the root).

   - Sound: Tense, unstable, and dissonant.

   - Example: B diminished triad (B - D - F).

Augmented Triads - Mysterious Sounds

Augmented triads consist of a root note, a major third, and an augmented fifth. The sound of augmented triads is mystical, unresolved, and slightly eerie, due to the augmented fifth (eight semitones) interval. This chord type is less common but is used to add an element of surprise or otherworldliness to a musical piece. An example of an augmented triad is the C augmented triad, which includes the notes C, E, and G#.

4. Augmented Triads

   - Construction: Root, major third, augmented fifth (8 semitones above the root).

   - Sound: Mystical, unresolved, and unstable.

   - Example: C augmented triad (C - E - G#).

Suspended Triads - Open Sounds

Suspended triads replace the third interval with either a perfect fourth or a major second, creating an open, unresolved sound that generates a sense of anticipation. Suspended 4th (sus4) triads consist of the root, perfect fourth, and perfect fifth, while suspended 2nd (sus2) triads include the root, major second, and perfect fifth. These chords are often used to create a feeling of suspension or to transition smoothly between other chords. Examples include the C sus4 (C, F, G) and the D sus2 (D, E, A).

5. Suspended Triads

   - Construction: Root, perfect fourth (suspended 4th) or major second (suspended 2nd), perfect fifth.

   - Sound: Open, unresolved, and creating a sense of anticipation.

   - Examples: 

     - C suspended 4th (C - F - G).

     - D suspended 2nd (D - E - A).

By exploring these various types of triads, musicians can enrich their harmonic vocabulary and create a wide range of emotional and atmospheric effects in their compositions.

Seventh Chords - 4 Note Chords

Although seventh chords contain the number “7”, they actually contain only 4 notes. Seventh chords add an extra layer of complexity and richness to basic triads by incorporating a fourth note: the seventh interval above the root. This addition transforms the triad into a more textured and sophisticated harmony, often used to create tension, resolve progressions, or add depth to a musical piece. Seventh chords are pivotal in jazz, classical, and contemporary music, providing a wide palette of emotional and harmonic colors. The specific interval between the root and the seventh note determines the type of seventh chord and its distinct sound and function within a progression.

Major Seventh Chords (maj7)

Major seventh chords are formed by adding a major seventh interval (eleven semitones) to a major triad. The combination results in a smooth, jazzy, and luxurious sound that is both consonant and rich. Major seventh chords are often used to convey sophistication and relaxation, frequently appearing in genres such as jazz and bossa nova. An example of a major seventh chord is Cmaj7, consisting of the notes C, E, G, and B.

1. Major Seventh Chords

   - Construction: Major triad plus major seventh (11 semitones above the root).

   - Sound: Smooth, jazzy, and luxurious.

   - Example: Cmaj7 (C - E - G - B).

Minor Seventh Chords (min7)

Minor seventh chords are created by adding a minor seventh interval (ten semitones) to a minor triad. This chord type produces a warm, mellow, and introspective sound, blending the minor triad's somber tone with the added seventh for a fuller harmonic texture. Minor seventh chords are prevalent in jazz, blues, and various forms of popular music to evoke depth and emotion. An example of a minor seventh chord is Am7, which includes the notes A, C, E, and G.

2. Minor Seventh Chords

   - Construction: Minor triad plus minor seventh (10 semitones above the root).

   - Sound: Warm, mellow, and introspective.

   - Example: A minor7 (A - C - E - G).

Dominant Seventh Chords (7)

Dominant seventh chords consist of a major triad plus a minor seventh interval. This structure generates a bright, bluesy sound with a strong sense of tension that naturally seeks resolution, often to a tonic chord. Dominant sevenths are fundamental in creating harmonic progressions, particularly in blues, rock, and jazz. An example of a dominant seventh chord is G7, comprising the notes G, B, D, and F.

3. Dominant Seventh Chords

   - Construction: Major triad plus minor seventh.

   - Sound: Bright, bluesy, and creates a strong resolution.

   - Example: G7 (G - B - D - F).

Diminished Seventh Chords (dim7)

Diminished seventh chords are formed by adding a diminished seventh interval (nine semitones) to a diminished triad. The result is a highly tense, dissonant, and unstable sound, making these chords effective for building dramatic tension and leading into more stable harmonies. Diminished sevenths are commonly used in classical and film music for their dramatic impact. An example of a diminished seventh chord is Bdim7, consisting of the notes B, D, F, and Ab.

4. Diminished Seventh Chords

   - Construction: Diminished triad plus diminished seventh (9 semitones above the root).

   - Sound: Highly tense, dissonant, and unstable.

   - Example: B diminished7 (B - D - F - Ab).

Half-Diminished Seventh Chords (min7b5)

Half-diminished seventh chords, also known as minor seven flat five (m7b5), are constructed by adding a minor seventh interval to a diminished triad. These chords have a dark, unresolved sound that is less dissonant than fully diminished sevenths, often used to create subtle tension in jazz and classical music. An example of a half-diminished seventh chord is Bm7b5, including the notes B, D, F, and A.

5. Half-Diminished Seventh Chords (Minor 7 flat 5)

   - Construction: Diminished triad plus minor seventh.

   - Sound: Dark, unresolved, and less dissonant than fully diminished sevenths.

   - Example: Bm7b5 (B - D - F - A).

Advanced Seventh Chords

The following chords are a little more advanced but can still be found in various styles of music pretty frequently. Although they are a little more difficult to use, they provide more interesting flavors and widen the possibilities of harmony. Keep an eye out for them to see how they function in songs. The best way to learn them is to see them in action.

Seventh Suspended Chords (7sus)

Seventh suspended chords are formed by adding a minor seventh interval to a suspended triad. This combination produces an open, unresolved sound with a mix of tension and anticipation, often used to create a sense of movement or transition. Seventh suspended chords are popular in rock, pop, and jazz. An example of a seventh suspended chord is G7sus4, which includes the notes G, C, D, and F.

6. Seventh Suspended Chords

   - Construction: Suspended triad plus minor seventh.

   - Sound: Open, unresolved, with a combination of tension and release.

   - Example: G7sus4 (G - C - D - F).

Minor Major Seventh Chords (min(maj7))

Minor major seventh chords combine a minor triad with a major seventh interval. This creates a unique, tense sound that blends the minor triad's melancholic quality with the major seventh's dissonance. These chords are less common but are used to add an exotic or unresolved feel in jazz and film music. An example is the A minor major seventh chord, consisting of the notes A, C, E, and G#.

1. Minor Major Seventh Chords

   - Construction: Minor triad plus major seventh.

   - Sound: Tense and somewhat exotic.

   - Example: A minor major7 (A - C - E - G#).

Augmented Major Seventh Chords (aug7 or 7#5)

Augmented major seventh chords consist of an augmented triad plus a major seventh interval. The result is a lush, surreal, and slightly dissonant sound that adds a sense of mystery and otherworldliness. These chords are typically used in jazz and contemporary classical music to create a striking and unexpected harmonic color. An example is the C augmented major seventh chord, which includes the notes C, E, G#, and B.

2. Augmented Major Seventh Chords

   - Construction: Augmented triad plus major seventh.

   - Sound: Lush, surreal, and slightly dissonant.

   - Example: C+maj7 (C - E - G# - B).

Dominant Seventh Flat Five Chords (7b5)

Dominant seventh flat five chords are created by adding a minor seventh interval to a major triad with a diminished fifth. This chord type produces a unique tension, often used in jazz to add a distinctive harmonic flavor. An example of a dominant seventh flat five chord is G7b5, comprising the notes G, B, Db, and F.

3. Dominant Seventh Flat Five Chords

   - Construction: Major triad plus minor seventh plus diminished fifth.

   - Sound: Unique tension and often used in jazz.

   - Example: G7b5 (G - B - Db - F).

Know Your Chords!

Understanding chords is fundamental to mastering music theory and practice. Triads, with their simplicity and variety, provide the basic building blocks of harmony, while seventh chords add depth and complexity to musical compositions. Each type of chord, from the bright major triads to the dissonant diminished sevenths, contributes uniquely to the emotional and harmonic landscape of a piece. By studying and utilizing these chords, musicians and composers can craft rich, evocative musical narratives that resonate with listeners on a profound level.