Augmented Major 7th

Notes and formula

The formula is 1 – 3 – ♯5 – 7, or 0 – 4 – 8 – 11 in semitones. A major seventh chord whose fifth has been raised, or equally an augmented triad that has kept the leading tone.

The chord holds two semitone frictions at once — B against the C above it, and G♯ against the A that the raised fifth suggests. Neither is a tritone, so nothing in the chord actually pulls; the tension is colour rather than direction.

How to play it

On piano it is C–E–G♯–B, and it wants a wide spread: root low, seventh high, the raised fifth somewhere in the middle where it can be heard as a colour.

On guitar the movable form with the root on the sixth string is 8–x–9–9–9–x, sounding C–B–E–G♯. There is no comfortable open-position version, which is part of why the chord is rare in guitar-written music.

Where it comes from

The augmented major seventh is the tonic of the Lydian augmented scale — the third mode of melodic minor — and that is the context in which jazz musicians meet it. Build a seventh chord on the third degree of A melodic minor and this is the result.

It also appears at the end of a chromatic ascent: a major seventh chord whose fifth rises to the sixth passes through this sonority on the way, and composers hold it there when they want the ascent to be heard.

Where you hear it

Impressionist writing uses it for weightlessness, jazz for the sound of a tonic that refuses to settle, and film scoring for wonder — the chord under a wide shot of something vast is very often this one.

It is uncommon in popular song for a simple reason: it does not support a melody easily. Both altered notes are semitones away from notes a singer would naturally reach for.

Augmented major seventh or augmented seventh

CaugMaj7 is C–E–G♯–B; Caug7 is C–E–G♯–B♭. The triad is the same and the seventh is not, and that one semitone decides whether the chord is a dominant.

Caug7 contains a tritone between E and B♭, so it pulls toward F. CaugMaj7 contains none and pulls nowhere. Charts distinguish them as maj7♯5 and 7♯5, and the difference is worth reading carefully.

Scales that contain it

Lydian augmented is the default: it contains every chord tone and adds a raised fourth, which suits the chord's brightness. The whole-tone scale contains the triad but not the major seventh, so it does not fit here as it does over aug7.

Where the chord is a passing sonority in a chromatic line, players usually ignore scales altogether and follow the moving voice — which is what the ear is following anyway.

Frequently asked questions