I came across several guitar chords which seem to be 'diminished' chords:
- X°
- X°7
- Xø
- Xø7
I read some articles which might provide useful informating, including the Dutch Wiki article Chord (music), and several others.
According to the caption Chord symbols and terminology from the Wiki article Half-diminished seventh chord, the symbol ø is invented to distinct a diminished triad plus a minor seventh and a diminished triad plus a diminished seventh.
I came to the following:
- According to this webpage, Cø is C – E♭ – G♭ – B♭.
- According to the Dutch Wiki article, C° is C – E♭ – G♭.
- According to that same article, Cø7 is C – E♭ – G♭ – B♭.
- C°7 is C – E♭ – G♭ – B♭♭.
But wait. Both Cø and Cø7 are mentioned, but they exist of the same notes. What is the difference between those two chords?