Introduction to Chords

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Chapter 5 · Lesson 01

In short

A chord is three or more notes sounding together. The most basic one is the triad, built from three notes stacked a third apart, one on top of the other. Depending on the quality of those thirds you get four types: major, minor, augmented, diminished.

Lesson Notes

Until now we worked with notes and intervals separately. The chord is the next step: two thirds stacked one on top of the other give us a group of notes that sound at the same time.

01What a triad is

A triad consists of three notes. The first, lowest note is called the root. From there you go up a third and find the chord's third. From the third you go up another third and find the fifth.

Example: the C major chord is C-E-G. C is the root, E is the third (a third above C), G is the fifth (a third above E).

02Major and minor chords

These are the two most common types. Their difference is which third sits on the bottom.

In the major chord the lower third (root to third) is major (2 tones) and the upper one (third to fifth) is minor (1½ tones). The result sounds bright. Example: C-E-G.

In the minor chord the lower third is minor (1½ tones) and the upper one is major (2 tones). The sound turns darker. Example: C-E♭-G.

Major and minor chord

C major

C-E-G · bright

C minor

C-E♭-G · dark

In both, the root is C and the fifth is G. Only the third changes: natural E (major third) in the major chord, E♭ (minor third) in the minor chord.

03Augmented and diminished chords

The remaining two types are rarer and have a more tense sound.

The augmented chord has two major thirds. The fifth is raised by a semitone compared to the major chord. Example: C-E-G♯.

The diminished chord has two minor thirds. The fifth is lowered by a semitone compared to the minor chord. Example: C-E♭-G♭.

Augmented and diminished chord

C augmented

C-E-G♯ · two major thirds

C diminished

C-E♭-G♭ · two minor thirds

The augmented chord uses two major thirds (C-E and E-G♯), the diminished two minor ones (C-E♭ and E♭-G♭). Both sound less stable than the first two.

Recap

The triad has three notes: root, third, fifth, built from two thirds stacked one on top of the other.
Major: major third below + minor third above (C-E-G). Bright sound.
Minor: minor third below + major third above (C-E♭-G). Darker sound.
Augmented: two major thirds (C-E-G♯). Tense, open sound.
Diminished: two minor thirds (C-E♭-G♭). Tense, compressed sound.