The Definition of Harmony
In simple terms, harmony is what occurs when more than one note is played or sung at the same time.
This can be as an interval (two notes, also called a dyad), or chords of three or more notes.
One way to think about harmony is that it deals with the ‘vertical’ aspects of music, whereas melody and rhythm deal with ‘horizontal’ aspects.
As you can see in the example below, only on the final two beats of the measure does harmony appear, and it’s easy to see because there are notes stacked ‘vertically’ on top of each other.
Consonance and Dissonance
Just because two simultaneous pitches produce a harmony does not mean they sound ‘harmonious’ together.
Harmony is simply whatever sound they do produce, and a ‘harmonious’ sound means something pleasant or nice sounding.
Harmony can be nice sounding – and the term for this is called consonance.
However, it can also sound rough or irritating, which is what we call dissonance.
Consonant intervals and chords produce a feeling of calmness and of rest.
Intervals that are considered consonant are unison (both people playing the same note) and octaves,
Perfect 5ths and 4ths (G – D or G – C), major and minor 3rds (F – A or F – Ab), and major and minor 6ths (D – B or D – Bb).
Also, the compound versions of these intervals are consonant as well.
Here are all the consonant intervals from middle C:
The major and minor triad chords are also consonant because they’re made of all consonant intervals.
For example, in a C Major triad (C – E – G), the C – E interval is a consonant major 3rd, the E – G interval is a consonant minor 3rd, and the C – G interval is a consonant Perfect 5th.
Most songs begin and end on consonant intervals and chords, because consonance is generally considered ‘relaxed’, and when you play consonant harmonies they don’t feel like they have to ‘go’ anywhere.
Whether a piece is in a major or minor key, it will most likely start and end with consonance (except in jazz and film music, both of which are genres that are based around dissonant chords rather than consonant).
Dissonant intervals and chords produce a feeling of tension and movement.
Intervals that are considered dissonant are major and minor 2nds (C – D or C – Db), major and minor 7ths (B – A# or B – A), and augmented and diminished 4ths and 5ths (F – B or F – C#), and the compound versions of them.
Here is a list of the dissonant intervals from Middle C:
One weird thing about this is that the Aug5 (C – G#) and Dim4 (C – Fb) intervals are enharmonically equivalent to the consonant intervals min6 (C – Ab) and Maj3 (C – E), respectively.
However, when they are written as diminished or augmented intervals they are dissonant, and only when they are written with the correct letters for the major/minor intervals are they consonant.
For example, in C# Major, the interval C# – F is dissonant (Dim4) but the interval C# – E# is consonant (Maj3).
Dissonant chords and intervals are usually found in between consonant ones, and rarely for very long.
They are inherently less ‘stable’ than consonant chords, and so usually when you play a dissonant chord it ‘resolves’ to a consonant chord.
Close vs Open Harmony
When playing a chord, you can play it in either what is called close or open harmony.
Close harmony is, like it implies, when the notes of a chord are close together.
So, if you start with the root of a chord (the note the chord is based on), then the next closest note you can play is the 3rd above the root.
From the 3rd, the next closest note you can play is the 5th, and from the 5th the next note is the 7th, and so on.
Open harmony is when the notes in a chord are more spaced out, and uses compound versions of intervals, like 10ths and 12ths instead of 3rds and 5ths.
Here is a C Maj 7 chord (C – E – G – B) written in close and open harmony:
Even though they are both made of the same notes, the two chords above sound different because one is tight and close together, and the other is very open and spanning multiple octaves.
How Harmony Works
Most music you listen to is called tonal music, which means it’s music that is centered around a single tone, called the tonic note (see our post on scale degrees for more info if you need).
In the key of C Major or Minor, the tonic note is the C, and the chord that is built on C (C Major or C Minor, respectively) is called the tonic chord.
In tonal music, there are three categories that chords fall into, based on their function in a song: tonic, dominant, and predominant.
A tonic chord is a chord that is stable, and one that feels like you don’t have to move anywhere from it.
Besides the main tonic chord that we mentioned above, other chords that could function as tonics are the iii chord (so an E Minor chord in the key of C Major) and a vi chord (A Minor).
A dominant chord is the opposite of a tonic chord.
It is a chord you want to move away from, and usually comes right before a tonic.
The two chords that are dominant chords are a V (G Major in the key of C Major) and a vii (B dim in the key of C Major)
A predominant chord usually bridges the gaps between tonic and dominant, and adds color to a chord progression.
There are two predominant chords – the ii (D Minor in the key of C Major) and the IV (F Maj).
Here’s an example chord progression that shows the proper function of the tonic, predominant, and dominant chords, in the key of E Major:
- I – tonic
- ii – predominant
- IV – predominant
- V – dominant
- vi – tonic
- vii – dominant
This was a very quick overview of how harmony functions in tonal music.
Those are the basic elements of harmony!
It is a very, very deep and detailed topic to get into, but we hope this was a helpful introduction.
Harmony informs almost all of music theory, and essentially is the basis of musical analysis for every type of music, from classical to jazz to pop music.
The Different Types Of Chords You Should Know
Chords are the basic building block for music harmony, and therefore you’ve almost definitely heard a lot about them. But there are a lot of different kinds of chords, and not many people know exactly what they are and how to make them.
Let’s take a look at all the different types of chords, but first, what is a chord?
What is a chord?
The definition of a chord is a group of two or more notes played at the same time.
These notes will usually compliment each other which then creates harmony.
On top of the harmony you’ll then have a melody played.
Different types of chords
We can categories chords in a number of different ways.
One way to sort them is by how many different notes each chord has which results in them having a different name.
Let’s take a look at what chords are called if they have two, three, four, or more notes.
Two note chords: Dyads
A chord that consists of only two notes is called an interval or a dyad.
Any two combinations of notes can technically be considered a dyad, but the most common ones you see have an interval of a 3rd between them.
For example, a dyad of C – E would be one that suggests a key of C major, because it contains two of the three notes of a C major triad chord.
So let’s take a look at triad chords next.
Three note chords: Triads
Triads are the most common type of chord in music.
They are made up of three notes which is why they’re called triads.
The “tri” in triad comes from the Greek word meaning “three”, which is where we get words like triathlete and triangle.
Triads are built using three particular notes: the root, 3rd and 5th with each note being an interval of a 3rd apart.
For example here is a C major triad with each interval between the notes being a 3rd.
Four note chords: Tetrads
Chords with four notes in are called tetrads.
The word “tetra” means “four” in Greek and is from the same root as tetrahedron (a shape with four faces).
There are few different types of tetrads with the most common type being seventh chords but we’ll cover these and some others later in this post.
Just like with scales, the type of chord you play depends on the intervals between each note.
We call this the quality of the chord.
The quality of the chord affects how it sounds for example you could say a major chord sounds happy, or a minor chord sounds sad.
Let’s take a look at the five types of chord quality.
A major chord is one that has a note that is a major 3rd (4 semitones) away from the root of the chord.
So in a C major chord you would expect to see an E in the chord, in an A major chord you would see a C#.
The octave and order of the notes don’t matter very much, for example the following chords are all E major triads:
If you have a major 7th chord or extended chord, the 3rd and the 7th have to be major.
Just like with major triads, what makes a minor triad minor is that there is a note in the chord that is a minor 3rd (3 semitones) away from the root of the chord.
For example here is C minor chord and you can see that the interval between the 1st and 2nd notes are a minor 3rd.
In a tetrad or extended chord, both the 3rd and 7th need to be minor but we’ll talk about those a bit later on when we look at extended chords.
A diminished chord that is made up of minor 3rd intervals.
So not only are the 1st and 2nd notes a minor 3rd apart, but the 2nd and 3rd are also a minor 3rd.
This means that it also has a diminished 5th interval (6 semitones) in it.
A C Minor chord would have C – Eb – G, but the diminished chord flattens the G to a Gb.
For a diminished 7th chord you have two options:
- A half diminished chord
- A fully diminished chord
A half-diminished chord keeps the minor 7th, so it therefore would have the notes C – Eb – Gb – Bb.
A fully diminished flattens the minor 7th down a step to become enharmonically equivalent to a major 6th (9 semitones).
A C fully diminished 7th chord would be made up of C – Eb – Gb – Bbb (B double flat, equivalent to an A).
The opposite of a diminished chord, an augmented chord is when you take a major chord and raise the 5th one semitone so that it is 8 semitones away from the root.
This way it’s made up of two major 3rd intervals (where as a diminished has two minor 3rd intervals).
For example, here is a C augmented triad:
Other types of chords
There are few other types of chord that you might need to know about. These types of chord are very common in jazz music.
A seventh chord gets its name because it uses the 7th scale degree.
As we said above, a triad chord uses the root note, the 3rd scale degree, and the 5th scale degree to make a chord.
So if an E major scale is E – F# – G# – A – B – C# – D# – E, then the E major triad would be the 1st, 3rd, and 5th letter: E – G# – B.
A seventh chord adds an extra note to the triad, and the note that it adds is the 7th scale degree.
So a C major 7 chord is: C – E – G -B: