Aeolian (Natural Minor)

The notes

E F♯ G A B C D, then E. It is the relative minor of G major and shares its single sharp; the notes are identical, only the centre of gravity moves.

The seventh degree, D, sits a whole tone below E — the weak leading note characteristic of the natural minor. Music that wants a stronger pull raises it to D♯, giving the harmonic minor and turning the B minor chord into B major.

On the fretboard

In open position the scale spans two octaves using four open strings, which no other minor key allows. The E minor pentatonic at the open position — the first scale most rock guitarists learn — is this scale with two notes removed.

The chords are Em, F♯ diminished, G, Am, Bm, C, D. Only Bm needs a barre, and it is frequently replaced by B7 or played as a partial shape.

Where it is used

Rock, metal and folk in equal measure. The key gives the instrument its deepest available tonic, which is why riff-based music gravitates here and to A minor.

Em–C–G–D is arguably the most played four-chord loop on the instrument, and all four chords are open shapes drawn from this scale.

The scale also explains a quirk of guitar tuning: drop D lowers the sixth string to D, the seventh degree of E minor, which is why so many riffs in this key move between the open low string and the note a tone above it.