Chords
G# Half-diminished
G# · B · D · F#
The half-diminished seventh — a diminished triad with a minor seventh. The ii of a minor key.
Also written G#ø · G#ø7 · G#-7b5 · G#h7 · G#h
G# Half-diminished
G# · B · D · F#
Voicings on the piano
| Voicing | Notes | Play it on your instrument |
|---|---|---|
| Closed, root position | G#3 · B3 · D4 · F#4 | |
| Open (drop 2) | D3 · G#3 · B3 · F#4 | |
| Shell | G#3 · B3 · F#4 | |
| Rootless | B3 · D4 · F#4 · G#4 |
Tap a key or a fret to hear it.
Anatomy
G# Half-diminished (G#m7b5) contains the notes G# · B · D · F#, each with a role measured as an interval from the root.
Read on: how triads are built · seventh chords
Inversions
An inversion of G# Half-diminished puts a chord tone other than G# in the bass; the name after the slash is that bass note.
Where it lives
The keys and the scales G# Half-diminished belongs to.
In which keys
G# Half-diminished is diatonic to 3 keys; the numeral is its degree and the label its harmonic function.
Scales that contain it
G# Half-diminished fits inside these scales, each built on G#.
- G# Minor BluesG# · B · C# · D · D# · F#
- G# LocrianG# · A · B · C# · D · E · F#
- G# Locrian PentatonicG# · B · C# · D · F#
- G# Super Locrian PentatonicG# · B · C · D · F#
- G# Locrian #2G# · A# · B · C# · D · E · F#
- G# Locrian 6G# · A · B · C# · D · E# · F#
- G# Bebop LocrianG# · A · B · C# · D · D# · E · F#
- G# Composite BluesG# · A# · B · B# · C# · D · D# · E# · F#
Understanding the G# Half-diminished chord
Names and symbols
G#m7b5 is the chord symbol for G# Half-diminished; it is also written G#ø, G#ø7, G#-7b5, G#h7, G#h.
The half-diminished seventh is written m7♭5 on charts and ø7 (or just ø) in jazz notation; both name the same four notes. It is not the diminished seventh, °7, whose seventh is a semitone lower.
How it is built
On G# it is G# · B · D · F#, stacking 1P · 3m · 5d · 7m. It is written m7♭5 or with the ø symbol, and both mean the same thing: a diminished triad softened by a minor rather than a diminished seventh.
How it is used
It is the ii of a minor ii–V–i, which makes it one of the most frequently played chords in jazz despite sounding exotic in isolation. It is also the chord built on the seventh degree of a major scale.
Unlike the fully diminished seventh it is not symmetrical, so it has a clear home and a clear direction: down a fifth, to the dominant.
Learn this properly
Chapter 10: Chords: Triads and SeventhsCommon questions
- What notes are in G#m7b5?
- G#m7b5 contains G# · B · D · F#. Name any set of notes with the chord identifier.
- What is the difference between half-diminished and fully diminished?
- The seventh. Half-diminished uses a minor seventh; fully diminished lowers it again to a diminished seventh, which makes the chord symmetrical.
- Where is a half-diminished chord used?
- As the ii of a minor ii–V–i, and as the chord built on the seventh degree of a major scale.
- What notes are in the G# Half-diminished chord?
- The G# Half-diminished chord contains the notes G# · B · D · F#: the root G# with the intervals 1P, 3m, 5d, 7m stacked above it. Play them together for the chord or one after another for an arpeggio. The lowest note is normally G#, but any chord tone can take the bass in an inversion.
- What intervals make up the G# Half-diminished chord?
- Measured from G#, the G# Half-diminished chord stacks the intervals 1P, 3m, 5d, 7m. The quality of the third and of the seventh, if there is one, is what gives the chord its character; the rest of the notes colour it. Every interval in the formula links to its own page, with its sound.