Sointuvuus

Sointuvuus is a Finnish term that denotes the perceptual quality of harmony or consonance in sound. It refers to how well tones blend when sounded together or in succession, creating a sense of unity, stability, or agreement. The word combines sointu, meaning tone or harmony, with the suffix -vuus indicating a characteristic or state.

In music theory, sointuvuus is closely related to consonance and dissonance. Consonant intervals—such as unison, octave, and perfect fifth—are typically experienced as stable and agreeable, while dissonant intervals—such as seconds, sevenths, and certain complex intervals—tend to introduce tension that seeks resolution. The perceived level of sointuvuus depends on frequency relationships, psychoacoustic factors, and cultural conventions. The harmonic series provides a natural basis for consonance, and tuning systems influence how strong this property feels. Just intonation often yields stronger sointuvuus for common intervals, whereas equal temperament slightly adjusts those ratios to accommodate modulation between keys, which can alter the immediacy of perceived consonance.

Sointuvuus is also affected by timbre, voice leading, dynamics, and balance within an ensemble. In composition and arrangement, choices about harmony, chord progressions, and texture shape the overall impression of sointuvuus. Across musical traditions, conceptions of consonance and harmony vary, so the standard of sointuvuus is not universal but context-dependent.