Gérard Grisey

Spectralism is a movement in contemporary classical music that treats timbre and the acoustic spectrum as primary compositional materials. Rather than building music from abstract pitch-class sets or functional harmony, spectral composers derive harmonies, orchestrations, and formal processes from the real-world spectra of sounds. Using tools such as Fourier analysis, they decompose a sound into its partials and then re-synthesize or orchestrate those partials across instruments, often employing microtonality, extended techniques, and slow, morphing processes. The result is music where color, resonance, and perceptual phenomena shape structure as much as melody or rhythm.

Microtonal classical is a stream of Western art music that organizes pitch using intervals smaller than the conventional 12-tone equal temperament. Composers employ alternative equal temperaments (such as 19, 24, 31, or 72 tones per octave), just intonation, and other tuning systems to expand harmony, melody, and timbre beyond the familiar semitone grid. The genre foregrounds novel intervals, complex chordal spectra, continuous pitch (glissandi), and fine-grained intonational nuance. It can sound otherworldly, tense, or delicately shimmering, and often requires specially retuned instruments, extended techniques, or custom-built instruments to realize its pitch language.

Classical music is the notated art-music tradition of Europe and its global descendants, characterized by durable forms, carefully codified harmony and counterpoint, and a literate score-based practice. The term “classical” can refer broadly to the entire Western art-music lineage from the Medieval era to today, not just the Classical period (c. 1750s–1820s). It privileges long-form structures (such as symphonies, sonatas, concertos, masses, and operas), functional or modal harmony, thematic development, and timbral nuance across ensembles ranging from solo instruments to full orchestras and choirs. Across centuries, the style evolved from chant and modal polyphony to tonal harmony, and later to post-tonal idioms, while maintaining a shared emphasis on written notation, performance practice, and craft.