key term - Diminished seventh chord

Definition

A diminished seventh chord is a type of four-note chord built by stacking two minor thirds on top of each other, resulting in a diminished triad plus a diminished seventh. This chord creates a tense and dissonant sound, often used to create tension in music and resolve to more stable chords.

5 Must Know Facts For Your Next Test

1. A diminished seventh chord can be constructed from any note as its root, creating multiple enharmonically equivalent chords (for example, C diminished seventh is the same as B# diminished seventh).
2. The intervals within a diminished seventh chord are symmetrical, allowing for easy transposition to different keys without changing the chord structure.
3. In tonal music, diminished seventh chords typically function as dominant chords that resolve to the tonic or other stable chords, enhancing the sense of movement in a piece.
4. The dissonance of a diminished seventh chord can heighten emotional intensity in music, making it particularly effective in dramatic or suspenseful contexts.
5. Composers often use diminished seventh chords in modulation to create smooth transitions between keys, as their symmetrical nature allows them to fit into various harmonic contexts.

Review Questions

• How does the construction of a diminished seventh chord relate to the characteristics of triads?
  • A diminished seventh chord is constructed by stacking two minor thirds on top of each other, which differentiates it from other seventh chords. This construction begins with a diminished triad consisting of a root, minor third, and diminished fifth. By adding another minor third above the diminished triad to form the diminished seventh, it showcases how this specific chord type builds upon the foundational principles of triadic harmony.
• In what ways do diminished seventh chords serve functional roles in harmonic progressions?
  • Diminished seventh chords typically function as dominant chords that resolve to tonic or more stable chords. Their tension and dissonance drive the music forward and create a sense of urgency that compels resolution. For example, a C diminished seventh chord can lead smoothly to an F major or D minor chord. This functional aspect is crucial for composers seeking to enhance the narrative or emotional journey of their pieces.
• Evaluate the impact of using diminished seventh chords on emotional expression in musical compositions.
  • Diminished seventh chords play a significant role in emotional expression due to their inherent dissonance and tension. They create an atmosphere of suspense or drama, often used in moments of conflict or climactic points within a piece. This impact is magnified through their versatility in modulation; composers utilize them to seamlessly transition between keys while maintaining emotional intensity. The ability of these chords to evoke strong feelings makes them a powerful tool in a composer's arsenal.

Related terms

Diminished triad:

A triad consisting of a root, a minor third, and a diminished fifth, forming the basis of the diminished seventh chord.

Seventh chord: A chord that consists of four notes: the root, third, fifth, and seventh, which can be major, minor, diminished, or augmented.

Tension and resolution: The concept in music where dissonance creates tension that seeks resolution in consonance, often illustrated by the use of diminished seventh chords leading to more stable chords.