Theory & harmony
Mode
A mode is a scale defined by which degree of a parent scale it starts on, playing the notes of C major from D to D gives Dorian, from G to G gives Mixolydian.
Seven modes come from the seven starting points of the major scale: Ionian (the major scale itself), Dorian, Phrygian, Lydian, Mixolydian, Aeolian (the natural minor), and Locrian. Each has a distinctive interval pattern above its own tonic, and that pattern, not the parent scale, is what the ear hears.
Modes matter to a string player because a great deal of folk-derived and twentieth-century orchestral writing is modal rather than major or minor. A passage with a key signature of one sharp that never resolves to G and keeps landing on D is Dorian, and recognising that stops you hearing it as a piece in the wrong key.
Vaughan Williams, Bartók, Debussy, and most film scoring lean heavily on modal colour, as does virtually all fiddle repertoire.
Related terms
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