A#m9♭5 — A# minor ninth flat fifth chord
A half-diminished seventh chord with the ninth added. Four minor thirds apart in the lower voices, with the ninth on top.
- 1 = A#
- b3 = C#
- b5 = E
- b7 = G#
- 9 = B#
- Symbol
- A#m9♭5
- Root
- A#
- Quality
- Minor ninth flat fifth
- Family
- extended
- Notes
- A# C# E G# B#
- Degree formula
1 b3 b5 b7 9- Semitones from the root
0 2 3 6 10- Distinct pitch classes
- 5
- Interval structure
- Stacked from the root: 3 semitones, 3 semitones, 4 semitones, 4 semitones
- Notation
- Written m9♭5. The ii chord of a minor ii-V-i when the ninth is wanted.
- Key
- A# · Bb major / G minor key signature
Fingering charts
The library holds 4 fingerings of this chord and all of them are shown, in the library’s own order. Several fingerings of one chord is normal: the same notes can be stopped at different positions and on different strings.
Formula
The chord tones in order from the root, with the interval each one forms above it.
| Degree | Note | Semitones | Interval from the root |
|---|---|---|---|
| 1 | A# | 0 | Perfect unison |
| b3 | C# | 3 | Minor third |
| b5 | E | 6 | Tritone |
| b7 | G# | 10 | Minor seventh |
| 9 | B# | 2 | Major second |
Inversions
An inversion is the same set of notes with a different one in the bass. The last column gives the distance of each note above the bass note, in semitones.
| Inversion | Bass note | Degree in the bass | Notes above the bass | Semitones above the bass |
|---|---|---|---|---|
| root position | A# | 1 | A# – C# – E – G# – B# | 0 3 6 10 2 |
| first inversion | C# | b3 | C# – E – G# – B# – A# | 0 3 7 11 9 |
| second inversion | E | b5 | E – G# – B# – A# – C# | 0 4 8 6 9 |
| third inversion | G# | b7 | G# – B# – A# – C# – E | 0 4 2 5 8 |
| fourth inversion | B# | 9 | B# – A# – C# – E – G# | 0 10 1 4 8 |
Playable voicings
These shapes were found by searching the fretboard of a standard-tuned guitar (E A D G B E) rather than copied from a chord book. The search allows every string to sound or to be muted, rejects any shape with a muted string between two sounding strings, rejects any shape whose fretted notes span more than four frets (a five-fret window), requires every chord tone to be present, and then sorts what remains with root-position shapes first and the most compact, lowest shapes next. The shapes shown are the first six of that ordering; other orderings are possible at the same frets.
| # | Shape (low string first) | Notes | Degrees | Bass | Span (frets) | Sounding strings |
|---|---|---|---|---|---|---|
| 1 | 6-4-6-5-5-4 | A# C# G# C E G# | 1 b3 b7 9 b5 b7 | A# | 2 | 6 |
| 2 | 6-4-6-5-5-6 | A# C# G# C E A# | 1 b3 b7 9 b5 1 | A# | 2 | 6 |
| 3 | 6-3-6-6-5-4 | A# C G# C# E G# | 1 9 b7 b3 b5 b7 | A# | 3 | 6 |
| 4 | 6-3-6-6-5-6 | A# C G# C# E A# | 1 9 b7 b3 b5 1 | A# | 3 | 6 |
| 5 | 6-7-6-6-5-8 | A# E G# C# E C | 1 b5 b7 b3 b5 9 | A# | 3 | 6 |
| 6 | 6-7-6-6-9-8 | A# E G# C# G# C | 1 b5 b7 b3 b7 9 | A# | 3 | 6 |
Shape numbers run from the lowest string to the highest, so the left-hand number is the sixth string (low E) in standard tuning. Multiple shapes are listed because a chord can be voiced several ways, and because a lower position is not always the better sounding one.
Related chords and scales
- KeyEverything in A#
- ScaleA# locrian
- ChordA#m7b5
- ChordA#m
- ChordA#m7
Related
- ChordA#m7b5 — Half-diminished seventh
- ChordA#m — Minor
- ChordA#m7 — Minor seventh
- ChordA#11 — Dominant eleventh
- ChordA#13 — Dominant thirteenth
- ChordA#9 — Dominant ninth
- DegreesBb — degree map
- Neck mapBb — note map