# The four main seventh chords

*Module 10 · Lesson 1: Seventh chords · BazzLow*

> Build and name major 7th, dominant 7th, minor 7th and half-diminished chords.

Before this lesson: [7.4 Chord symbols](https://bazzlow.com/en/triads-and-arpeggios/chord-symbols/) · [8.1 Diatonic triads](https://bazzlow.com/en/harmony-in-a-key/diatonic-triads/)

A triad has three notes. Put one more third on top and you get a seventh chord, the everyday harmony of jazz, soul, funk and much pop.

## Triad plus a 7th

A **seventh chord** is a triad plus the **7th** above the root, a third stacked on the 5th. It has four notes, **1 3 5 7**, and the qualities vary. These are the four main types, from C:

*The four main seventh chords from C.*

| Chord | Formula | Notes | Stacked thirds | Site symbol (EN / IT) | Other forms |
| --- | --- | --- | --- | --- | --- |
| major 7th | 1 3 5 7 | C E G B | M3 m3 M3 | Cmaj7 / Do maj7 | CM7, CΔ7, CΔ, Do 7+ |
| dominant 7th | 1 3 5 ♭7 | C E G B♭ | M3 m3 m3 | C7 / Do 7 | — |
| minor 7th | 1 ♭3 5 ♭7 | C E♭ G B♭ | m3 M3 m3 | Cm7 / Do m7 | Cmin7, C−7 |
| half-diminished | 1 ♭3 ♭5 ♭7 | C E♭ G♭ B♭ | m3 m3 M3 | Cø7 / Do ø7 | Cm7♭5 |

> **Diagram:** Cmaj7: C E G B.

> **Diagram:** C7: C E G B♭.

> **Diagram:** Cm7: C E♭ G B♭.

> **Diagram:** Cø7: C E♭ G♭ B♭.

## Reading the symbols

- In **Cmaj7**, “maj” describes the **7th**: a major triad with a major 7th.
- In **Cm7**, “m” describes the **triad**: a minor triad with a ♭7.
- A plain **7** (C7) always means a ♭7 on a major triad: the **dominant seventh**.

The interval between the root and the 7th is a **major 7th** (11 semitones, one fret below the octave) or a **minor 7th** (10 semitones, two frets below the octave). On the bass, the ♭7 is two strings up at the same fret as the root (lesson 4.3).

Seventh chords sound richer and less “final” than triads. The dominant 7th in particular wants to move (lesson 10.4). The Chords for Bass tool shows all four types on every root.

## Try it

Play 1–3–5–7 arpeggios of Cmaj7, C7, Cm7 and Cø7 one after the other. Then do the same from G (fret 3 on the E string).

## New terms

- seventh chord
- major seventh chord
- dominant seventh chord
- minor seventh chord
- half-diminished chord

Page: https://bazzlow.com/en/seventh-chords/four-seventh-chords/