Half-Diminished Seventh Chord

Definition

A half-diminished seventh chord is a four-note chord consisting of a root, a minor third, a diminished fifth, and a minor seventh. This chord is often represented by the symbol 'ø7' and has a distinct sound that can create tension and resolution in harmonic progressions. Its unique structure sets it apart from other seventh chords and allows it to play a vital role in both major and minor tonal contexts.

5 Must Know Facts For Your Next Test

1. The half-diminished seventh chord is built by stacking a minor third on top of a diminished triad followed by another minor third on top of that.
2. In terms of scale degrees, in a minor key, the half-diminished seventh chord is typically found on the seventh scale degree.
3. It serves as a crucial pivot point in harmony, particularly in ii-V-I progressions within both major and minor keys.
4. The half-diminished seventh chord creates a unique sense of tension that often resolves to a tonic or dominant chord.
5. This chord can also function as a leading tone chord in major keys or as an altered dominant chord in jazz contexts.

Review Questions

• How does the structure of the half-diminished seventh chord contribute to its function in harmonic progressions?
  • The half-diminished seventh chord's structure of a root, minor third, diminished fifth, and minor seventh creates a unique blend of tension due to its dissonant intervals. This tension often seeks resolution, making it effective in progressions like ii-V-I where it naturally leads to the tonic. The inclusion of both minor and diminished intervals provides a distinct sound that enhances emotional expression in music.
• Compare the half-diminished seventh chord with the fully diminished seventh chord in terms of their harmonic roles and uses.
  • While both chords contain similar intervals, the half-diminished seventh chord features a minor seventh interval, whereas the fully diminished seventh chord includes a diminished seventh. This difference makes the half-diminished chord more stable and versatile for use in common harmonic progressions. In practice, the half-diminished chord often serves as a leading tone chord or ii chord in minor keys, while the fully diminished chord tends to create more intense tension before resolving to stable harmonies.
• Evaluate how the use of half-diminished seventh chords can impact musical compositions across different genres.
  • The incorporation of half-diminished seventh chords across various musical genres can significantly enhance harmonic depth and emotional complexity. In classical music, they often serve as important transitional chords that build tension before resolving. In jazz, their use can add sophisticated color to improvisation and composition. The ability to evoke feelings of suspense or anticipation makes them essential tools for composers aiming to engage listeners emotionally while creating intricate harmonic structures.

Related terms

Diminished Seventh Chord: A diminished seventh chord consists of a root, a minor third, a diminished fifth, and a diminished seventh, creating an intense and unstable sound often used for dramatic effect.

Seventh Chord: A seventh chord includes four notes: the root, third, fifth, and seventh, which can be major, minor, dominant, or diminished, each providing different harmonic functions.

Tension and Resolution: Tension and resolution refer to the musical principle where dissonance (tension) is resolved into consonance (resolution), creating movement and emotional impact within a piece.