Minor 7 vs Min7♭5 (Half-Diminished)
The C minor 7 and the C min7♭5 (half-diminished) share 3 notes — C, Eb, Bb. From there, the C minor 7 adds G, while the C min7♭5 (half-diminished) adds Gb.
Piano, C3 to C5. Notes in this scale, low to high: C3 (root of C Minor 7 and root of C Min7♭5 (Half-Diminished)), Eb3 (flat 3 of C Minor 7 and flat 3 of C Min7♭5 (Half-Diminished)), Gb3 (flat 5), G3 (5), Bb3 (flat 7 of C Minor 7 and flat 7 of C Min7♭5 (Half-Diminished)), C4 (root of C Minor 7 and root of C Min7♭5 (Half-Diminished)), Eb4 (flat 3 of C Minor 7 and flat 3 of C Min7♭5 (Half-Diminished)), Gb4 (flat 5), G4 (5), Bb4 (flat 7 of C Minor 7 and flat 7 of C Min7♭5 (Half-Diminished)), C5 (root of C Minor 7 and root of C Min7♭5 (Half-Diminished)).
Both scales above are drawn on one piano keyboard in the key of C. Notes belonging to both are drawn as a split two-color dot, so the notes they share and the notes unique to each are visible in one picture.
How the formulas differ
Scale degrees are the key-independent way to compare two scales — these stay the same in every key, and they are what actually distinguishes one scale from another.
| Scale | Degrees |
|---|---|
| Minor 7 | R · b3 · 5 · b7 |
| Min7♭5 (Half-Diminished) | R · b3 · b5 · b7 |
Notes in common
| Note | In Minor 7 | In Min7♭5 (Half-Diminished) |
|---|---|---|
| C | R | R |
| Eb | b3 | b3 |
| Bb | b7 | b7 |
Notes that differ
- Only in the minor 7: G (5)
- Only in the min7♭5 (half-diminished): Gb (b5)