Seventh Chords & Extended Harmony
Adding a fourth note to a triad creates a seventh chord — richer, more colorful, and essential to jazz, pop, and classical music. This week deepens your harmonic vocabulary.
Learning Goals
Lesson Content
Types of Seventh Chords
A seventh chord adds a note a seventh above the root to a triad:
- Major 7th (Cmaj7): C-E-G-B — Major triad + Major 7th. Dreamy, sophisticated.
- Minor 7th (Cm7): C-Eb-G-Bb — Minor triad + Minor 7th. Mellow, jazzy.
- Dominant 7th (C7): C-E-G-Bb — Major triad + Minor 7th. Bluesy, wants to resolve.
- Diminished 7th (Cdim7): C-Eb-Gb-Bbb(A) — Diminished triad + Diminished 7th. Very tense.
Diatonic 7th Chords in C Major
- Imaj7: Cmaj7 (C-E-G-B)
- ii7: Dm7 (D-F-A-C)
- iii7: Em7 (E-G-B-D)
- IVmaj7: Fmaj7 (F-A-C-E)
- V7: G7 (G-B-D-F)
- vi7: Am7 (A-C-E-G)
- vii7b5: Bm7b5 (B-D-F-A)
The ii-V-I Progression
The most important progression in jazz: Dm7 → G7 → Cmaj7. The ii7 creates gentle tension, the V7 creates strong tension, and the Imaj7 resolves it beautifully. Learning to hear this movement is a milestone in your musical development.
Practice Activities
Activity 1: Play Seventh Chords
On the Synthesizer, build each 7th chord from C. Compare Cmaj7, Cm7, C7, and Cdim7. Then play the ii-V-I progression: Dm7 → G7 → Cmaj7. Let each chord ring for 4 beats.
Activity 2: Chord Identification — Advanced
Move to Advanced difficulty in the Chord Identification game. This mode may include 7th chord qualities and inversions. Push for accuracy at this new challenge level.
Activity 3: Advanced Note Reading
Move to Advanced difficulty in Note Reading with Both clefs. Try challenging key signatures like E major (4#) or Ab major (4b). You should be reading fluently in any key by now.
Activity 4: Chord Reading — Advanced
Move to Advanced difficulty in the Chord Reading game. Read 7th chords and complex voicings on the staff. This challenges you to quickly identify chord quality from dense notation.