A# Augmented Chord
Mysterious, dreamy sound
The lowest A#aug shape sits at fret 6 (6th-string root — 6th fret). It's one of 3 voicings mapped across the neck.
A#aug · 6th-string root — 6th fret
What is a A#aug chord?
An augmented chord stacks the root, major 3rd and raised 5th (#5). Like the diminished chord, both interval gaps are equal — but in this case, two major 3rds. The result is symmetrical and rootless-feeling: any of the three notes could plausibly be the root. Augmented chords feel suspended, dreamy, lifting — never fully resolved.
Notes in the chord: A# – D – F#
Intervals: Root, 3, #5 (measured from the root)
Where A#aug fits in a key
A#aug appears as the I in A# major.
Common progressions with A#aug
I-V-vi-IV — in A# major
A# → F → Gm → D#
I-IV-V — in A# major
A# → D# → F
I-vi-IV-V — in A# major
A# → Gm → D# → F
When to use a augmented chord
A#aug works as a chromatic lift out of A# on the way to D#. Use augmented chords as a chromatic step inside a I → I+ → IV motion (e.g. C → Caug → F) — the raised 5th becomes the major 3rd of F, creating smooth voice leading. They appear constantly in jazz, blues turnarounds (the V+ before a I), and any genre wanting that suspended, lifting quality (think Beatles 'Oh Darling' intro, or 60s Bond themes).
Common substitutions for A#aug
- •Augmented 7 (7#5) — adds a flat 7 for a dominant-augmented sound that resolves like V7
- •Whole-tone-derived voicings — augmented + 9 is rooted in the whole-tone scale
- •Plain major — drop the #5 if the moment calls for stability
Improvisation Basics
Learn to solo over progressions
Practice with Improvisio
Use A#aug in a progression and see which scales work best.
Try it in the trainer