Introduction to Harmony

We have already learned that melody refers to pitches played in sequence. Harmony, on the other hand, deals with pitches sounded simultaneously. To put it another way, melody is the horizontal aspect of pitch, and harmony is the vertical aspect.

Harmonies can be used to add support and depth to a melody, or sometimes harmony is simply the result of many melodies overlapping each other (as in polyphony). Harmony is also important for the form (large-scale organization) of musical works and can be used to give long pieces a sense of unity and structure.

Consonance and Dissonance

Some harmonies sound pleasing and stable, while others clash and seem unstable. The stable harmonies are called consonant, while the unstable harmonies are called dissonant. Consonant harmonies give a sense of serenity and rest to a piece, while dissonant harmonies create tension and anxiety. Each style of music has its own conventions about how consonance and dissonance are managed and therefore which harmonies are preferred.

The perfect intervals (unison, octave, perfect 4th, and perfect 5th) are considered the most consonant intervals. The most dissonant intervals are a half step away from the perfect intervals: minor 2nd, major 7th, and tritone (also called augmented 4th or diminished 5th). The other intervals fall somewhere in between, with the major 2nd and the minor 7th being somewhat dissonant, and the major and minor 3rds and 6ths being somewhat consonant.

Interval Name
(Perfect) Unison
minor 2nd, half step
Major 2nd, whole step
minor 3rd
Major 3rd
Perfect 4th
tritone (augmented 4th, diminished 5th)
Perfect 5th
minor 6th
Major 6th
minor 7th
Major 7th
(Perfect) Octave

Dissonant harmonies can make listeners feel unsettled and tense. This tension makes listeners wish for the release and resolution of consonant harmonies. When dissonant harmonies change to consonant ones, it is called resolution. Longing for resolution can give music a sense of forward momentum, and the way that resolutions are granted or withheld can make listeners feel either satisfied or frustrated. Just as some stories are left unresolved, so are some harmonies. For more about harmonic resolution, see Cadences.

Consonant and Dissonant Harmonies

"Music is nothing else but wild sounds civilized into time and tune." - Thomas Fuller

"After silence, that which comes nearest to expressing the inexpressible is music." - Aldous Huxley

"Music in the soul can be heard by the universe." - Lao Tzu

"Music is a higher revelation than all wisdom and philosophy." - Ludwig van Beethoven

"Music is the movement of sound to reach the soul for the education of its virtue." - Plato

"Music expresses that which cannot be said and on which it is impossible to be silent." - Victor Hugo

"Music is nothing else but wild sounds civilized into time and tune." - Thomas Fuller

Copyright © Sienna M. Wood, 2015-2022