7th Chords
A# Half-Diminished 7th chord
A diminished triad with a minor seventh, also written m7♭5. The classic ii chord of a minor key ii–V–i.
Notes in A# Half-Diminished 7th
| Note | Interval | Semitones from root |
|---|---|---|
| A# | Root | 0 |
| C# | Minor 3rd | 3 |
| E | Tritone | 6 |
| G# | Minor 7th | 10 |
Formula: 0–3–6–10 semitones above the root. Move the whole shape up or down and you get the same chord in another key — that is why Half-Diminished 7th chords sound alike no matter where they start.
Other chords on A#
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