The Aeolian scale, also known as the natural minor scale, is one of the seven musical modes and is characterized by its dark, somber, and emotive sound. It is widely used in various musical genres, including classical, rock, pop, and metal.

Construction:

The Aeolian scale is built using the following interval pattern:

• Whole step

• Half step

• Whole step

• Whole step

• Half step

• Whole step

• Whole step

In A Aeolian, it would be:

• A (root)

• B (whole step)

• C (half step)

• D (whole step)

• E (whole step)

• F (half step)

• G (whole step)

• A (octave)

Features:

• Minor tonality: The Aeolian mode has a minor tonality, characterized by a minor third (between the root and the third degree), which gives it a melancholic or reflective quality.

• Lowered sixth and seventh degrees: Compared to the major scale, the Aeolian mode has a flat sixth and a flat seventh, contributing to its darker, more introspective sound.

Chord Construction:

• Tonic chord (i): A minor (A, C, E)

• Supertonic chord (ii°): B diminished (B, D, F)

• Mediant chord (III): C major (C, E, G)

• Subdominant chord (iv): D minor (D, F, A)

• Dominant chord (v): E minor (E, G, B)

• Submediant chord (VI): F major (F, A, C)

• Subtonic chord (VII): G major (G, B, D)

Usage:

• Classical Music: The Aeolian mode has been used extensively in classical music to evoke a sense of melancholy, tragedy, or introspection.

• Rock and Metal: The scale is a cornerstone in rock and metal music, providing the dark, powerful sound that defines many songs in these genres.

• Folk Music: Many traditional and folk songs are written in the Aeolian mode, giving them a rustic, sometimes haunting quality.

• Film Scores: Composers use the Aeolian scale in film scores to underscore dramatic, sorrowful, or reflective scenes.

The Aeolian scale is fundamental in Western music and is often the go-to scale when a piece or song requires a minor key with a straightforward, unembellished emotional impact.