Music Theory

Music Theory

Music theory is a broad term used to describe a lot of things. Music theory has a long history and many different themes which are exciting to delve into. Relevant topics could be:

  • What influence have different books about music theory had on our way of composing music?
  • When can you call a chord for a 'chord' and not just a collection of notes?
  • Why do some things sound good and some things sound bad?

We won't be able to go through it all here since there is enough material for a university education! We will though go through the most important rules and music theory which is good to know if you want to understand western music - especially if you want to learn to play an instrument.

Music Theory can be hard to wrap your head around, so don't be put off. If you need a tutor to help you discover this new language, you're in the right place:

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What Are Chords?

A chord is created when multiple different notes ring out simultaneously. There has to at least three different notes (even though power chords only have two!). Chords are most often built up of stacked thirds. That means that a major or minor third lies between the other notes.
All songs consist of a basic melody and some chords. The chords back up the melody; one could say that they colour and support it. Major and minor chords are the most normal - these are actually what the fundamentals of most music is made of.

How Do I Read A Chord Symbol?

When writing down chord symbols you follow a more ore less fixed order: First you state the tonic, then wether it is a major or minor chord (if it is a major chord you do not write anything, if it is a minor you write a lower case m). Then wether it has any extensions and then (most often in parenthesis) if it has any alterations. At the you can write modifications to the bass note after a forward slash. Here are some examples:

  • Cm7(b5) = C is the tonic, m indicates that it is a minor chord, 7 means that it has been extended with a seventh and (b5) meaning that the fifth is diminished.
  • Abmaj7/C = Ab is the tonic, there is an m but it is part of maj7 meaning that the chord has been extended with a major seventh. At last there is a /C meaning that the bass note has been changed to a C

*If there is no m behind the chord it is a major chord. You do not write Cmajor - maj7 is an indication that the chord contains a major seventh. 

Circle Of Fifths

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The circle of fifths is a tool which can be used for multiple things: It shows the signature of a key and what major and minor chords a key belong in that key.

For a more detailed explanation of the circle of fifths, see our page here: Circle of Fifths

Relative Key Signatures

Looking at relative keys, the outer part of the circle of fifths shows major keys and major chords whereas the inner par shows minor keys and minor chords. The major and minor chords which are opposite to each other, e.g. C and Am er relative keys.

What Are Harmonies?

In this paragraph you can read about the three most common types of harmonies, namely functional harmony, modal harmony and blues harmony. You can also read about affinity, which helps when determining what type of harmony is used in a piece of music, and the characteristics of each type of harmony.
The term harmony deals with what type of chords are used in a piece of music - and what the relationship between the chords are. If you are doing a harmonic analysis you must first find out what type of harmony is used. A distinction is often made between three types of harmony: functional, modal and blues harmony.
They can be set up in this triangle. A piece of music will almost always find itself somewhere in this triangle: it can be all out functional harmony or maybe in between functional harmony and modal harmony. Maybe it is mostly modal but with hints of blues.


Affinity means 'relationship' and concerns the relationship between two chords. There are three types of affinity which can be part of determining what kind of harmony is being used in a piece of music:

Descending Fifths

Descending fifth affinity means that from one chord up to the other is an interval of a fifth (or a fourth if going down) - e.g. in the sequence G-C

Leading Note Affinity

Leading tone affinity means that a chords third is leading tone to the next chords tonic. In the sequence G-C there is both descending fifth affinity and leading tone affinity, because the G's third b leads to the C's tonic: c. There is also such a thing as downward leading tone affinity from the chord's small seventh to the following chord's third, e.g. G7-C where the G7's small seventh f leads to the C's third.

Common Note Affinity

Common-tone affinity is about two chords containing some of the same notes. The chord sequence G-C has some common-tone affinity because both of them contain the note g (as the tonic and the fifth). In the chord sequence C-Am7 there is more common-tone affinity because three of the notes are the same: (C) C-E-G and (Am7) A-C-E-G.


In this paragraph you can read about the names of the notes. This is important because when you know their names you can start learning other things: reading sheet music, reading scales and get a better understanding of intervals and chords.

The Names Of The Notes

Notes without accidentalsOverall there are 12 different notes. Out of the 12, 7 have been given a letter as a name. These are the notes without accidentals
a – b – c – d – e – f – g
Between these are a whole tone - except between b and c and then again between e and f. Between these are only a semitone. This is why, on a piano, there are some white keys which are directly beside each other while others have black keys between them,

Between The Notes: # and ♭

The rest of the notes are seen as semitone above or beneath the seven notes. These are the notes which are marked with a or a ♭. The♭is called  flat and the is called sharp (not a hashtag!). If a # is added to a note, a sharp will be added to the end and vice versa for ♭. You can see all the 12 notes and how they are pronounced:


In this paragraph you can read about the most important scales and get an understanding of them.
Just like the fundamental major and minor keys and major and minor chords there are also fundamental major and minor scales. If you are playing piano it is easiest to learn the C-major scale - it consists of all the white keys! When you have learnt the C-major you have actually also learnt the A-minor scale. They consist of the same notes because they are relative keys

What Is A Scale?

Scale i latin for 'stair' and is used in many contexts, e.g. the Richter scale, the pH scale or even just 'on a scale from 1 to 10'. In music it is a bit different though. It refers to 'stairs' or a sequence of notes which fit together in a certain key.

What Do I Use Scales For?

You can use scales for many songs. For example, when writing a song it can be nice to what notes you are 'allowed' to use and which of them are outside the scale. When playing a solo you will know what notes sound good and which do not.

How To Find Relevant Music Education

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