Aeolian

Seven modes from seven notes

The article The modes through familiar pieces explains how the modes arise: if you play only the white keys on the piano from C to C, C major sounds. If you play the same keys from A to A, Aeolian sounds. They are the same notes with a different reference point, and so the semitone steps lie in different places relative to the tonic.

According to the article, Ionian is identical to major, Aeolian identical to natural minor. The other five modes are what is usually meant when modes are spoken of.

The missing leading tone

In natural minor a whole tone lies between the seventh degree and the tonic, in A minor between G and A. The article The leading tone describes the consequence: the dominant would be E–G–B, a minor triad, and that does not pull. The page Identify Scales sums it up as a listening feature: with natural minor the character is decided by the missing leading-tone tension. Hear the ending with Em:

The ending with Em sounds softer and more open than the ending with E major. How the leading tone is introduced afterwards in minor is described under Harmonic minor.

Playing modally means holding the reference note

The article on the church modes stresses: a mode arises not from the choice of notes but from the emphasis. If you play the white keys over a drone on A but keep ending the phrases on C, you have C major again, although no note is different. On the guitar, open strings are ideal for this: a held bass note with melody notes above it immediately sounds like the mode, without a second musician being needed.

Common mistakes

• Understanding Aeolian and natural minor as opposites: They are two names for the same scale.
• Losing the reference note: Without a drone, bass note or clear phrasing nobody hears the mode, only a scale with a shifted starting point.
• Mixing Aeolian with harmonic minor: If you play G♯ instead of G, you leave Aeolian and land in harmonic minor.