The half-diminished chord is built by stacking a minor third, diminished fifth, and minor seventh above the root.
Half-diminished chords, also known as minor7(♭5) chords, play a crucial role in jazz harmony, especially when it comes to ii-V-I progressions in minor keys. The half-diminished chord is often found as the ii chord in these cadences, creating tension that resolves to the V7 chord.
For example, in the key of C minor, the ii-V-I progression would be:
Notice how the Dø7 chord adds a sense of tension and instability that makes the resolution to G7 and ultimately Cm7 sound even more satisfying.
To build a half-diminished chord, start with a minor seventh chord and lower the fifth by a half-step. So an Am7 chord (A-C-E-G) becomes an Aø7 chord (A-C-E♭-G).
Half-diminished chords can be built on any root note. Here are the spellings for all 12 half-diminished chords:
Practice these chords in all inversions and get comfortable with their unique sound. Listen for them the next time you're checking out your favorite jazz standards!
Try these exercises to get half-diminished chords under your fingers:
Happy practicing! Incorporating half-diminished chords into your playing will add a quintessential jazz sound to your harmonic palette.