Fifth

Definition

A fifth is a musical interval spanning five diatonic scale degrees. It is one of the most important intervals in tonal music, forming the basis for harmony, particularly in triads and seventh chords. The fifth can be either perfect, diminished, or augmented, and it serves as a key component in establishing tonality and the relationship between chords.

5 Must Know Facts For Your Next Test

1. The perfect fifth spans seven half steps, making it one of the most consonant intervals in music.
2. In a major triad, the fifth is found between the root and the highest note, creating a stable and harmonious sound.
3. The diminished fifth, also known as the tritone, is an interval that spans six half steps and has a dissonant quality often used for tension.
4. The augmented fifth consists of eight half steps and creates a feeling of instability, often leading to resolution in harmony.
5. Fifths are essential in constructing dominant seventh chords, which are crucial for establishing tension before resolving to the tonic.

Review Questions

• How does the perfect fifth function within a major triad?
  • In a major triad, the perfect fifth creates a strong sense of stability and consonance. The interval spans from the root note to the highest note of the triad, reinforcing the harmonic structure. This stable relationship allows major triads to sound complete and satisfying, playing a vital role in tonal music's harmonic framework.
• Compare and contrast the characteristics of perfect fifths with diminished fifths. How do these intervals affect musical tension?
  • Perfect fifths are consonant and stable, spanning seven half steps and creating harmony. In contrast, diminished fifths are dissonant and span six half steps, often described as the tritone. This tension introduced by diminished fifths can evoke feelings of unrest or suspense within a piece of music, making them effective in transition sections or climaxes.
• Evaluate the importance of fifths in constructing dominant seventh chords and their role in musical resolution.
  • Fifths play a critical role in forming dominant seventh chords by providing harmonic tension that seeks resolution. The inclusion of the perfect fifth alongside the root, third, and seventh notes enhances the chord's stability while simultaneously generating an urge to resolve back to the tonic chord. This characteristic is essential for establishing functional harmony within tonal music, guiding listeners' expectations and emotional responses throughout a composition.

Related terms

Triad: A triad is a set of three notes consisting of a root, a third, and a fifth, which together create a chord fundamental to Western harmony.

Seventh Chord: A seventh chord is a four-note chord that includes the root, third, fifth, and an additional note called the seventh, which adds complexity and depth to harmony.

Diatonic Scale: A diatonic scale is a seven-note scale that includes five whole steps and two half steps in each octave, forming the basis for Western music theory.