Chapter 3
You might wonder why we need minor keys. Haven't we covered enough with major keys in the previous sections?
Yes, we have discussed major keys, which account for about 75% of all music. However, minor keys make up the majority of the remaining 25% used in both classical and popular music.
Don't worry—we'll simplify minor keys using the innovative "Rectangle of Fifths" numbering system.
Much has been written about the emotional impact of music in major and minor keys. Music can evoke different emotions in each person, whether playing or listening. Generally, music in major keys is associated with feelings of joy, exhilaration, and positive, optimistic thoughts. On the other hand, music in minor keys often evokes sadness and memories of the past.
Many composers favor minor keys, and it's common for compositions to move between major and minor keys, adding variety, movement, and energy. These key changes, known as modulation, play on emotions and create a dynamic listening experience.
Modulation involves shifting between keys, often by moving between major or minor keys that share common chords or between a major key and its corresponding minor key. This technique is a powerful way to create emotional shifts in music.
Before diving into individual minor keys, we'll provide a brief overview of some basic music theory, essential for understanding how different types of keys are formed.
In the section on major keys, we introduced modes, starting with the Ionian mode, which produces the major scale used to form major keys. The major scale is a pattern that identifies the intervals between white notes, starting and ending on C.
If we applied this pattern starting and ending on other white notes, we would get six additional scale patterns. Along with the Ionian mode, these comprise the seven modes commonly used in music.
In this section we examine how the Aeolian Mode minor scale is formed.
Before we examine the Aeolian mode in detail, we will show the seven the different modes in music. Shown here are the seven different scale patterns that identify the black note intervals the separate each of the white notes in ascending order by starting and finishing with a different white note position. These seven scales are the seven Modes in music.
There is a unique scale pattern for each Mode.
Note:
To form a scale pattern for any white key tonic position mode: Start at a white tonic position and skip each black position in ascending order and select the next white note.
Relative Minor Keys
The major keys in the earlier section were based on the Ionian Mode scale pattern. The Ionian scale is a pattern that identifies the black note intervals that separate each white note by starting and finishing with the C white note.
We will only examine the Aeolian Mode in this section.
The Aeolian Mode pattern shows the pattern that identifies the black note intervals that separate each of the white note positions by starting and finishing with the white “A” note.
The Aeolian Mode scale pattern is known as the natural minor scale.
Starting and finishing with the white A note positions above, we show the pattern of black note intervals separating each white note. Just skip the black positions.
Select the Tonic A note position: Skip, No Skip. Skip, Skip, No Skip, Skip, Skip. This is natural minor scale pattern.
This pattern gives us the intervals as follows: T S T T S T T
Where T=Tone S=Semitone
Uniquely, relative minor keys, formed on the sixth scale degree position of its major key, produce the same notes and the same chords (in different scale degree positions) as its corresponding major key.
Both keys have the same key signature but have a different tonal centre (Tonic). The two keys are classified as being relative.
All major keys have a relative minor key which is formed on its sixth scale degree position note.
Parallel Minor Keys
A natural minor key has a unique relationship with its corresponding major key, known as a parallel minor key relationship.
Both keys share the same tonic note, meaning they have the same tonal center.
It is common for compositions in a minor key to borrow chords from their corresponding major key and vice versa. Compositions often move between parallel keys, which adds a richer variety of notes and chords compared to modulating between relative minor keys.
In parallel minor keys, the notes in the 3rd, 6th, and 7th scale degree positions shift down one step from their positions in the corresponding major key (explained in more detail below).
While parallel minor and major keys share the same tonic, they have different key signatures.
Relative Minor Keys
To change to a relative minor key, just change the tonal centre of a major key from the first scale degree position to the sixth scale degree position.
Both the major and relative minor keys have a different tonal centre.
Both the major and relative minor keys have the same key signatures.
Parallel Minor Keys
Major and their parallel minor keys have the same tonic note position.
For parallel minor keys, the notes in scale degree positions 3, 6 and 7 move back one position from their corresponding major key positions.
Both the major and its parallel minor keys have the same tonal center.
Both the major and its parallel minor keys have different key signatures.
Relative and Parallel Key Relationships
Let’s Recap:
Relative and Parallel Key Relationships are two fundamental concepts in music theory that describe different ways major and minor keys can be related to each other.
Relative Keys:
Definition: A pair of major and minor keys that share the same key signature but have different tonics (root notes).
Example: C major and A minor are relative keys. Both have no sharps or flats in their key signatures, but C major is based on the note C, and A minor is based on the note A.
Relationship: The relative minor of a major key is found by going down three half steps (or a minor third) from the tonic of the major key. Conversely, the relative major of a minor key is found by going up three half steps from the tonic of the minor key.
Parallel Keys:
Definition: A pair of major and minor keys that share the same tonic (root note) but have different key signatures.
Example: C major and C minor are parallel keys. Both are based on the note C, but C major has no sharps or flats, while C minor has three flats in its key signature.
Relationship: Parallel keys differ in their modes, with the major key being based on the Ionian mode and the minor key on the Aeolian mode. This difference in modes is what changes the key signature.
Summary:
Relative Keys: Same key signature, different tonic.
Parallel Keys: Same tonic, different key signature.
These relationships are crucial for understanding key changes, modulations, and the expressive possibilities in music composition and analysis.