Augmented chord - piano

The augmented chord is a triad composed of a root, a major third and an augmented fifth. Notated aug or +, it creates a characteristic ascending tension.

Intervals

Degree IIII♯V
Interval RootMajor thirdAugmented fifth
Semitones 048

Formula 1 - 3 - ♯5

Theory

The augmented chord is built with two successive major thirds (4 + 4 semitones). The augmented fifth (8 semitones) creates tension that calls for resolution. C augmented = C-E-G♯, D augmented = D-F♯-A♯. Like the diminished chord, it is symmetrical: each inversion produces another augmented chord.

Examples

Example: Do Augmented

Augmented chord diagram on piano - Bass fret 999

Styles

Jazz Classique Bossa Nova Rock progressif

Construction

Formula 1 - 3 - 5#: augmented fifth. Symmetrical structure.

How to play

3-4 string positions. Jazz, bossa nova, whole-tone use.

Learning

Explore whole-tone scale. Exercise: C - Caug - F.

Triad inversions on piano

On piano, inversions are fundamental for creating smooth progressions and avoiding bass leaps.

The 2 possible inversions

  • 1st inversion (sixth chord): third in bass (3-5-1), noted I6. Creates melodic bass lines.
  • 2nd inversion (six-four chord): fifth in bass (5-1-3), noted I6/4. Used as cadential chord or bass pedal.

Mastering inversions is essential for keyboard harmony: they keep voices close and avoid large leaps between chords.