Sävellajiin

Sävellaji (key) is a core concept in Western music theory that identifies the tonal center of a piece and the scale pattern that shapes its melodies and harmonies. A sävellaji determines which pitches are most closely associated with the music and how chords typically progress within that tonal framework.

In common use, sävellajit are mainly divided into major and minor. A major key (duuri) centers on a bright, stable sound built from the major scale. A minor key (molli) centers on a darker mood and uses the natural, harmonic, or melodic minor scales. Each major key has a relative minor that shares the same key signature, meaning they use the same set of sharps or flats but have different tonics (for example, C major and A minor).

Key signatures denote the accidentals required by a sävellaji and are written at the beginning of each staff. The arrangement of sharps and flats follows the circle of fifths, providing a compact way to transpose between keys. There are 15 distinct major/minor key signatures in the traditional Western system: one with no sharps or flats (C major / a minor), seven with sharps, and seven with flats. Each signature implies two related keys (a major and its relative minor).

Sävellajiin informs analysis, composition, and performance by guiding chord choices, cadences, and modulation. Pieces may move from one sävellaji to another through modulation, enhancing contrast and expression. Beyond major and minor, modal scales offer alternative tonal frameworks, though they are typically treated as separate systems in classical harmony.