A chord quality is the flavor of a chord: major (bright), minor (dark), diminished (unresolved), augmented (unstable), dominant seventh (bluesy pull), major seventh (jazzy warmth), minor seventh (lush minor), half-diminished (jazz cadence starter).

Learn the four triads first

1. Major triad (root, major third, perfect fifth). Sound: bright, resolved. Anchor: any hymn opening.
2. Minor triad (root, minor third, perfect fifth). Sound: dark, resolved. Anchor: House of the Rising Sun opening.
3. Diminished triad (root, minor third, diminished fifth). Sound: unresolved, needs to go somewhere. Anchor: the vii° chord in any major key.
4. Augmented triad (root, major third, augmented fifth). Sound: floating, ambiguous. Anchor: Oh! Darling by the Beatles (opening chord).

Then the seventh chords

1. Dominant 7th (major triad + minor seventh). Sound: bluesy, pulls to the tonic. Anchor: any 12-bar blues.
2. Major 7th (major triad + major seventh). Sound: jazzy, warm, floating. Anchor: Something by the Beatles (opening chord Cmaj7).
3. Minor 7th (minor triad + minor seventh). Sound: lush minor, softer than plain minor. Anchor: So What by Miles Davis.
4. Half-diminished 7th (diminished triad + minor seventh). Sound: unresolved, the ii chord in a minor key. Anchor: the opening of Wagner’s Tristan (contested, but iconic).

The daily drill

Ten minutes, five days a week. First five minutes: triad quality only. Second five minutes: mixed triads and sevenths. The free ear trainer supports both drills; set mode to chord-quality.

Common confusions

• Minor and diminished (both have a minor third). Diminished’s fifth is flatter; it sounds like it needs to move.
• Augmented and major (both have a major third). Augmented’s fifth is sharper; it sounds unstable.
• Minor 7th and dominant 7th (both have a minor seventh on top). The triad quality below is the tell.