The full set
Ordered below by Aubel's unlock progression, easiest disambiguation first. Every chord links to a full written guide, and hearing them reliably comes down to consistent practice.
- Major Triad with major 3rd and perfect 5th. The reference chord: bright, stable, resolved. Read the guide →
- Minor Triad with minor 3rd and perfect 5th. The defining "sad" color against major. Read the guide →
- Diminished Triad with minor 3rd and tritone (flat 5). Tense, unstable. The vii° of any major key. Read the guide →
- Augmented Triad with major 3rd and raised 5th. Symmetric; every inversion sounds the same. Read the guide →
- Dominant 7 Major triad plus a minor 7th. The tritone between 3 and flat 7 pulls strongly toward resolution. Read the guide →
- Major 7 Major triad plus a major 7th. The half-step between 7 and root gives the lush, unresolved sound. Read the guide →
- Minor 7 Minor triad plus a minor 7th. The smoothest 7th — minor sadness softened. Read the guide →
- Half-diminished Diminished triad plus a minor 7th. The classic ii° in a minor-key ii–V–i. Read the guide →
- Diminished 7 Stack of three minor 3rds. Symmetric like augmented but darker. Passing chord in classical voice-leading. Read the guide →
The four triads
Every common triad is one of four shapes, defined by the pair of 3rds you stack to build it.
Major is a major 3rd on the bottom and a minor 3rd on top. Bright, stable, the reference. Minor inverts that stack: minor 3rd on the bottom, major 3rd on top. Darker, also stable.
Diminished stacks two minor 3rds. The outer interval is a tritone, which is unstable, which is why the chord wants to resolve. Augmented stacks two major 3rds. The outer interval is an augmented 5th, also unstable, but the chord is perfectly symmetric and doesn't pull in any particular direction.
The five 7ths
Add a 7th on top of a triad and you get a 7th chord. The character depends on which triad you started from and which 7th you added.
Dominant 7 is a major triad plus a minor 7th. The tritone inside it makes it pull hard toward its resolution. Major 7 is a major triad plus a major 7th. The half-step between the 7th and the octave gives it a lush, unresolved feel. Minor 7 is a minor triad plus a minor 7th. The smoothest of the 7ths, common in soul and pop ballads.
Half-diminished is a diminished triad plus a minor 7th. Common as the ii chord in a minor-key ii-V-i. The 7th softens the chord noticeably compared to the bare diminished triad. Diminished 7 is three stacked minor 3rds, four notes all three semitones apart. Fully symmetric, darker than augmented, a useful pivot chord in classical and jazz writing.
How the game runs
Aubel plays all the notes of the chord simultaneously on a random root, then asks you to name it. The tile grid contains whatever chords are in your active pool. Rolling accuracy gates the next unlock. Major and minor start unlocked; the others come in the order shown above.