Harmony is the part of music that organizes different notes sounding at the same time.
Look at this very simple pop song. Each given moment you can hear 9 notes at the same time. The main melody, the bass line, a secondary melody made with a kind of flute sound, and 6 notes in the guitar chords.
It sounds well because all this simoultaneous elements are control by the rules of harmony.
This is the newest element in western music. There has been a long period of evolution to achieve the complex harmonic system that we have today. This evolution started before the 9th Century. The current harmony technics have not been fixed till the 17th century.
Most of musical traditions either inside or outside Europe have very simple harmonic systems.
To get a general idea about harmony please wacht this video before reading the information below.
3.1 Consonance and dissonance
Consonance and dissonance are the foundation of all harmonic systems. They refer to the two different feelings that can be produce by to notes sounding at the same time.
· Consonance: two consonant sounds sounding together produce a stable result. They perfectly melt together and is generally considered nice.
· Dissonance: Two simultaneous dissonant sounds produce a feeling of instability and unrest. We usually say that dissonances sound bad.
Two notes are consonant or dissonant depending on the interval between them. Some intervals are objectively consonant. Others on the contrary are not universally accepted. The consonant more used in Western music today wasn’t accepted as such till the 16th century. Because of that although they sound perfectly well for us they are called demi-consonances.
Here you have a table with the qualification of different intervals.
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Consonance |
8J, 5J, 4J |
|
Demi-consonance |
3, 6, mayor and minor |
|
dissonance |
All the rest |
Harmony uses combinations of
consonances and dissonances that sound well.
3.2 The chord
It is the basic unit of harmony. They are clusters of notes that are perceived as a unity. Chords are used to accompany melodies. The important notes of the melody have to be contained in the chord.
Chords are formed by superposition of intervals of 3th. The most common chord is the triad. It is formed by two 3th one upon the other. More 3th can be added, generating dissonances in the process. The dissonances don’t make the chord sound bad; they integrate in it instead making the chord more instable and dynamic.
Triad chords (all consonant)
7th Chords (one dissonance)
Some music styles use a lot of dissonant chords. Blues music for example introduces dissonances in all its chords. This use of dissonances creates a special feeling of movement and dynamism even in slow beats. Many rock styles have inherited that kind of chords.
Here you have an example of a tune were dissonances are present everywhere.
3.3 Chords progressions.
Chord progressions are sequences of chords used for reinforcing the feeling of open or closed ending of the melodic phrases.
· If the progression reinforces the closed ending is called cadence.
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· If the progressions reinforce the open ending are called half cadence or deceptive cadence.
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You can see an explanation of how chords progressions work comparing it with the traditional roles in a family pressented from a very conservative an religious American point of view. Maeby you don't share the values shown in the video but nevertheless is a very graphic way to explain chords progresions and teir relation with tonality.
(Subir subtitualado)
In this other one you can see the most usual chords progresions in modern music.
3.4 Texture
Musical texture is the way different melodic lines relate together.
Textures can be simplified in some basic types:
· Monophonic: There is only one melodic line. Many people can be singing or playing instruments at the same time but all of them are doing the same melody simultaneously.
It is the older and simplest one. It is used in Gregorian chant and in traditional music.
Gregorian chant
Trditional Irish music
· Drone texture: It is the simplest kind of harmony. It consist in accompanying a melody with a single note corresponding with the tonic (or more rarely with the dominant) of the scale. The backup note is called drone.
It is also very old and simple. Therefor is used in ancient and traditional music too. Many traditional instruments always sound that way, as happens with bagpipes and hurdy-gurdies. In traditional fiddle or in rabel music is usual to play two strings together for getting this particular texture.
Old roman chant
Bagpipes: Irish Uillean pipes
· Backed up melody: There are many melodies and notes sounding together but one of them is clearly detached while the others are accompanying with chords in the background. They support and embellish the main melody. It’s the newest form of texture. It made its apparition almost as we know it today in the Baroque Era. There are many notes sounding at the same time but only one important melody.
· Guitar ang song
Polyphonic: In this texture there are many different melodies sounding together but all of them are equally important. It is the more complex either from the composer as from the listener point of view. The listener has to share his attention among all the different simultaneous melodies. Historically this texture had its peak in the renaissance and Baroque music.
There are two particular cases of polyphonic texture:
- Imitative polyphony: Different voices use the same or similar melodic materials. It seem that different melodies are imitating (or chasing) each other.
The work Ave Maria of Josquin Despez is a good example of imitative polyphony. You can see the movement of the melodies in the score that goes along with the sound of the music.
- Homophony: All different melodies move at the same time. It gives a more powerful feeling of connection between melodies.
This is an example of homophony
You can add to these basic textures any kind of mixtures between them.
