The C# half-diminished / Db half-diminished chord (C#m7b5) is made of the notes C#, E, G and B. It is built from the root C# with a minor third, a diminished fifth and a minor seventh.
The half-diminished chord (m7b5) is the second-degree chord of minor keys; very common in jazz.
C# half-diminished
Notes: C# – E – G – B
Guitar — positions on the neck
Piano — root position and inversions
Fingerings and positions
On guitar, this chord can be played in 3 ways along the neck. It is most often played with a barre. Example fingering (from the low E string to the high E string, x = muted string): x4545x. On piano, the right hand plays 4 notes, in root position or in an inversion.
Notes and intervals
Note
Interval
C#
root
E
minor third
G
diminished fifth
B
minor seventh
In which keys? The C# half-diminished chord is the viiø7 of D major and the iiø7 of B minor.
What are the notes of the C# half-diminished chord?
The notes of the C# half-diminished chord (C#m7b5) are C#, E, G and B.
How do you play the C# half-diminished chord on guitar?
On guitar, this chord can be played in 3 ways along the neck. It is most often played with a barre. Example fingering (from the low E string to the high E string, x = muted string): x4545x.
How is the C# half-diminished chord built?
The C# half-diminished / Db half-diminished chord (C#m7b5) is made of the notes C#, E, G and B. It is built from the root C# with a minor third, a diminished fifth and a minor seventh.
Are C# and Db the same chord?
Yes: C# and Db are the same note (they are called enharmonic), so C# half-diminished / Db half-diminished is played exactly the same way, with the same fingerings.