Basics of Triads and Seventh Chords

2 minute read

It’s important to be familiar with your chords when playing jazz, because when reading jazz music the chords aren’t written out for you: the harmony is only given to you in the form of chord names.

• Intervals
• Triads
• Seventh Chords
• Inversions
• Final Note

Intervals

Before learning about chords, you need a brief knowledge of intervals. Intervals are used to name the spaces between two notes. Let’s call the distance between two adjacent keys on a keyboard a half-step. Then, the distance of one half-step is called a minor 2nd, two half-steps a major 2nd, three half-steps a minor 3rd, etc. All the intervals are laid out for you here with respect to C.

Triads

Triads are the most basic chord. They consist of three notes and are defined by the intervals between the notes. There are four kinds of triads: major, minor, diminished, augmented.

Above are respectively the major, minor, diminished, and augmented triads with the appropriate notation.

Major Triad

This triad consists of a major 3rd and then a minor 3rd.

Minor Triad

This triad consists of a minor 3rd and then a major 3rd.

Diminished Triad

This triad consists of a minor 3rd and then a minor 3rd.

Augmented Triad

This triad consists of a major 3rd and then a major 3rd.

Seventh Chords

Seventh chords consist of four notes. They are called seventh chords because they also include the seventh degree of the scale. There are five types of seventh chords commonly used in jazz.

The five types of seventh chords are major 7, dominant 7, minor 7, half-diminished 7, diminished 7. They are listed above respectively.

Major 7

This seventh chord consists of a major triad and then a major 3rd.

Dominant 7

This seventh chord consists of a major triad and then a minor 3rd.

Minor 7

This seventh chord consists of a minor triad and then a minor 3rd. It is also notated as Cm7.

Half-Diminished 7

This seventh chord consists of a diminished triad and then a major 3rd. It is also notated as C-7♭5 or Cm7♭5.

Diminished 7

This seventh chord consists of a diminished triad and then a minor 3rd.

Inversions

You can change the order of these chords too. These are called inversions.

Triad Inversions

Here are the inversions for the C Major triad.

Seventh Chord Inversions

Here are the inversions for the C Major 7 chord.

Final Note

Try making triads from each root note until you’re comfortable with each of them. Then move on to seventh chords. Then move onto inversions. Happy practicing!

Written on June 2nd , 2020 by Chris Cheung