What is a harmony?
In music, a harmony refers to two or more complementary notes played or sung at the same time. For example, a choir may sing in harmony, with one section singing the melody while other sections sing the accompanying harmony.
As another example, when playing the piano, the right hand will most likely play the melody (the main recognisable tune), while the left hand will simultaneously play complementary notes or chords that work with the key and melody, and therefore create the harmony.
What are the different type of harmonies and techniques?
Four-part harmonies are frequently used in music, with the parts separated into the different ranges of soprano, alto, tenor and bass. This configuration may be used in arrangements for choral music as well as string quartets, for example.
Four-part harmonies are also often used in music written for keyboard instruments, such as the piano. For example, the left hand may play a series of triad chords (which contain three notes – the root and the third and fifth intervals above it), while the right hand plays the melody.
Harmonies can have different structures. For example, a piece may include parallel harmonies (also known as parallel motion), which is where two voices (or parts) travel in the same direction (up or down the scale) with the same number of intervals (the jumps between notes – from B to G, for example).
Other types of harmony include similar motion, where both parts travel in the same direction but with different intervals.
Static motion involves both parts repeating notes – for example, part one may play B, B, while part two plays G, G.
Oblique motion involves one part travelling up or down the scale while the other part plays the same note repeated.
Meanwhile, contrary motion sees one part travelling up the scale, while the other part travels down the scale.
All of these harmony techniques are used to help create extra interest, texture and dimension to a piece of music.