Compare
Harmonic Minor vs Melodic Minor
Both add the leading tone to natural minor; only melodic minor also raises the 6th. The classical / jazz divide.
Harmonic Minor
R
♭2
2
♭3
3
4
♭5
5
♭6
6
♭7
7
Melodic Minor
R
♭2
2
♭3
3
4
♭5
5
♭6
6
♭7
7
What's different
Only in Harmonic Minor
♭6
Only in Melodic Minor
6
In both
R2♭3457
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