Melodic minor

The third form

The article The leading tone explains why it exists: harmonic minor has a distance of a tone and a half between the sixth and seventh degrees, which is disturbing in the course of a melody. That is why there is melodic minor. Ascending, the sixth and seventh degrees are raised, so that the melody runs smoothly to the root. Descending, where no leading tone is needed, it returns to the natural form. This asymmetry, according to the article, is no whim of theorists but the consequence of a single need: to have a semitone at the top, not at the bottom.

The exercise page Scale Ear Training describes the same idea: melodic minor additionally raises the sixth degree in order to smooth the leap of harmonic minor, classically only ascending. In ear training it comes in on higher levels after harmonic minor.

In the score

Piano

• Menuett g-Moll BWV Anh. 115, from the Notebook for Anna Magdalena Bach · piano · 1 page

  Two flats in the key signature. In bar 29 the right hand runs upwards D–E–F♯–G–A–B♭ with a natural sign before E and a sharp before F: in G minor these are the raised sixth and seventh degrees. The PDF notes that the piece is attributed to Christian Petzold.

• Armes Waisenkind Robert Schumann, op. 68 No. 6 · piano · 1 page

  “Lent”, 2/4, no sharps or flats in the key signature. At the beginning of the second part after the repeat sign the bass rises E–F♯–G♯–A: ascending in A minor with the raised sixth and seventh degrees.

Both examples show melodic minor as a fragment in a piece, not as a scale exercise. The raised notes appear as accidentals within the bar, not in the key signature.

Common mistakes

• Playing raised descending as well: Classically the scale returns to G and F descending.
• Confusing it with harmonic minor: In harmonic minor the sixth degree stays unchanged and the scale is the same in both directions.
• Forgetting the natural signs: Descending, G and F need a natural sign after the raised notes in the score.