Harmonic Minor

One raised note, and everything that follows from it

Natural minor in A is A B C D E F G. Raise the G to G sharp and two things change at once. First, the seventh degree now sits a semitone below the tonic and pulls towards it. Second, the gap between the sixth and the seventh degrees widens to three semitones — an augmented second, the interval that gives this scale its immediately recognisable colour.

The harmonic consequence is the whole point. In natural minor the chord built on the fifth degree is E minor, which does not lead anywhere in particular. With G sharp it becomes E major, or E7 with the seventh added, and the pull back to A minor becomes as strong as in a major key. Composers did not invent a scale and then write with it; they raised the note where they needed the cadence, and theory named the result afterwards.

The augmented second, and what it is not

Between F and G sharp there is a step of three semitones, larger than anything in the major scale. Sung or played, it is the sound most listeners label as exotic, and it is the reason this scale appears whenever film music wants to signal somewhere far from home. That association says more about western scoring habits than about the music being referenced.

It is worth being precise about the difference. The augmented second is a normal interval of twelve-tone equal temperament, playable on any piano. The traditions it is often used to evoke — Arabic maqam, Turkish makam — use pitches that sit between the keys of a piano and cannot be reproduced on one at all. Harmonic minor can resemble those traditions from the outside; it does not contain them.

Seven modes, and the one that matters

Like any seven-note scale, this one can be read from each of its degrees, producing seven modes. Most of them are specialist material, but the fifth — phrygian dominant — is used far more than the parent scale itself. Read A harmonic minor from E and you get E F G sharp A B C D: a major third with a flattened second above it, which is the sound of flamenco, of klezmer, and of a great deal of metal.

The practical takeaway for a guitarist is that learning the parent scale gives you the mode for free. The fingering is identical; only the note you treat as home changes. Practising phrases that resolve to E over an E7 chord and then the same shape resolving to A over A minor is the fastest way to hear that the two are one set of notes with two different centres of gravity.

The chords it produces

Harmonising the scale in thirds gives a set of chords found nowhere else: i minor, ii diminished, III augmented, iv minor, V dominant seventh, VI major and vii fully diminished seventh. Two of them are the reason to study the scale at all — the dominant seventh on the fifth degree and the diminished seventh on the seventh, both of which resolve to the tonic with more force than anything in natural minor.

This is also where the classical convention comes from. Minor-key music routinely uses natural minor for descending melodic lines, harmonic minor for the cadence and melodic minor for ascending ones, all inside a single phrase. Treating them as three separate scales to memorise misses the point; they are three states of the same key, chosen according to what the harmony needs at that moment.

How to practise it

On guitar the scale sits comfortably as three notes per string, and the augmented second falls under a stretch between the first and fourth fingers. That stretch is the whole technical difficulty, and it is why the neoclassical guitar vocabulary of the 1980s leans on this scale so heavily: the shape rewards fast alternate picking and sequenced patterns.

On the piano the fingering follows the natural minor with one adjustment, but the ear needs more work than the hand. Play a i-iv-V7-i progression, then improvise over it using natural minor everywhere except the bar with the dominant chord. Hearing the raised seventh appear exactly when the harmony asks for it teaches the scale better than running it in isolation ever will.

Frequently asked questions