A# Dominant 7th Chord
Bluesy tension that wants to resolve
A#7 is most commonly played as a movable barre chord — the easiest shape sits at fret 1 (Bb7 Barre).
A#dom7 - Bb7 Barre
What is a A#7 chord?
A dominant 7th adds the flat 7 to a major triad — root, major 3rd, perfect 5th and minor 7th. That flat 7 creates an unresolved tension (the tritone between the 3rd and the b7) that 'wants' to resolve down a fifth. This is the engine of every V-I cadence in jazz and the foundation of every 12-bar blues progression where every chord is dominant.
Notes in the chord: A# – D – F – G#
Intervals: Root, 3, 5, b7 (measured from the root)
Where A#7 fits in a key
A#7 appears as the V7 in D# major.
Common progressions with A#7
ii-V7-I (jazz turnaround) — in D# major
Fm → A#7 → D#
I7-IV7-V7 (12-bar blues) — in A# blues
A#7 → D#7 → F7
When to use a dominant 7th chord
A#7 has the strongest pull of any chord toward D# — it's the V7 of D# major. Dominant 7ths are the V chord in countless major-key songs, where they pull strongly back to the I (G7 → C in C major). In 12-bar blues, every chord is dominant — I7, IV7 and V7 — for that bluesy, unresolved cycle. They also appear as secondary dominants ('V of V') to tonicize chords mid-progression, e.g. D7 leading to G in C major.
Common substitutions for A#7
- •Dominant 9 — adds the 9 for a fuller, jazz-funk sound
- •Dominant 13 — adds the 13 for soul and gospel voicings
- •Altered dominant (7#5, 7b9) — for outside, jazz-fusion tension
- •Tritone substitution — replace V7 with bII7 for a chromatic resolution
Mixolydian Mode
Perfect for dominant 7th
A# Blues Scale
Add blues flavor
Improvisation Basics
Learn to solo over progressions
Practice with Improvisio
Use A#7 in a progression and see which scales work best.
Try it in the trainer