Minor, Augmented and Diminished Triads

Previously, we learnt that major chords are constructed using three notes from a given major scale. In this lesson we will look at how easy it is to alter the notes within a chord to create new qualities. The four qualities of triads that will be covered are major, minor, augmented and diminished.

Now that we understand how major chords are constructed, we can derive the remaining three basic triads by altering the notes of the major chord. When we alter the notes of a triad to create minor, diminished and augmented triads, we will either sharpen or flatten the 3rd or 5th or both notes by one half-step.

The Minor Triad

The minor triad can be constructed using the following methods:

1. By flattening the 3rd of the major triad by a half-step.

Creating a C Minor Triad by Lowering the 3rd of the Major Triad

The C Triad with a Flat 3rd

2. The first note of the minor triad is the root note of a given major scale. Moving 3 half-steps up from the root gives you the 2nd note of the chord. Moving up 4 half-steps from the 2nd note gives you the 3rd note of the chord.

Creating a C Minor Triad Using Steps

The C Triad created using half-steps or semitones

3. By taking the root note of a major scale and stacking a minor 3rd and a major 3rd on top.

Creating a C Minor Triad Using Interval Stacking

The C Triad created using half-steps or semitones

The Diminished Triad

The diminished triad can be constructed using the following methods:

1. By flattening both the 3rd and 5th of the major triad by a half-step.

Creating a C Diminished Triad by Lowering the 3rd and 5th of the Major Triad

The C Triad with a Flat 3rd and Flat 5th

2. The first note of the diminished triad is the root note of a given major scale. Moving 3 half-steps up from the root derives the 2nd note of the chord and moving up 3 half-steps from the 2nd note derives the 3rd note of the chord.

Creating a C Diminished Triad Using Steps

The C Diminished Triad created using half-steps or semitones

3. By taking the root note of a major scale and stacking a minor 3rd and another minor 3rd on top.

Creating a C Diminished Triad Using Interval Stacking

The C Diminished Triad created using half-steps or semitones

The Augmented Triad

The augmented triad can be constructed using the following methods:

1. By sharpening the 5th of the major triad by a half-step.

Creating a C Augmented Triad by Raising the 5th of the Major Triad

The C Augmented Triad with a Sharp 5th

2. The first note of the augmented triad is the root note of a given Major scale. Moving 4 half-steps up from the root derives the 2nd note of the chord and moving up 4 half-steps from the 2nd note derives the 3rd note of the chord.

Creating a C Augmented Triad Using Steps

The C Augmented Triad created using half-steps or semitones

3. By taking the root note of a major scale and stacking a major 3rd and another major 3rd on top.

Creating a C Augmented Triad Using Interval Stacking

The C Augmented Triad created using half-steps or semitones

Dealing with Accidentals

When we alter the notes of a triad, we must make sure we name the notes correctly.

  • When we flatten a natural note by a half-step it becomes a flat; b suffix
  • When we sharpen a natural note by a half-step, it becomes a sharp; # suffix
  • When we flatten a sharp note by a half-step, it becomes a natural
  • When we sharpen a sharp note by a half-step, it becomes a double sharp; x suffix
  • When we flatten a flat note by a half-step, it becomes a double flat; bb suffix
  • When we sharpen a flat note by a half-step, it becomes a natural