atonality
theoryay-toh-NAL-ih-tee
Music that lacks a tonal centre or key, avoiding the traditional hierarchy of pitches.
Atonality describes music that deliberately avoids establishing a key or tonal centre. In tonal music, all pitches relate to a central tonic, creating a hierarchy of tension and resolution. Atonal music abandons this hierarchy, treating all twelve chromatic pitches as equal. Arnold Schoenberg pioneered atonality in the early 20th century, moving beyond the extreme chromaticism of late Romantic harmony into music with no key signature and no sense of home key. His student Anton Webern carried atonality further into extreme brevity and purity. Schoenberg later systematised atonality through serialism and the twelve-tone technique, which organises all twelve pitches into a predetermined row. Atonal music can sound dissonant, unsettling, and expressionistic — qualities that made it ideal for conveying the psychological anxiety of the early 20th century. While controversial, atonality expanded the expressive range of music enormously.