Spectral music
A compositional movement since the 1970s drawing on the analysis of sound spectra (Grisey, Murail).
What it means
Spectral music is a compositional movement that arose from the 1970s onward, above all in France. Its starting point is the analysis of sound spectra, that is, the overtones that make up a sound, usually with the help of computer-aided sound analysis.
Rather than starting from traditional pitches, chords, or scales, the composition proceeds from these measured frequency ratios, which are then translated into musical material.
Musical use
Defining figures include Gérard Grisey and Tristan Murail, who co-founded the group L'Itinéraire in Paris in the early 1970s. Works such as Grisey's Partiels begin directly from the analysis of a single sound, for instance a trombone note, and unfold the entire composition from it.
Characteristic of spectral music are gradual shifts of timbre, microtonal gradations beyond the tempered semitone system, and a way of composing that treats sound and time more as structure and less as traditional melody or harmony.
Spectral music should be distinguished from serial music, which proceeds from abstract number series rather than acoustically measured sound spectra, and from electronic music in the narrower sense, even though both often use electronic tools for sound analysis or generation.
Performance practice
If you play spectral music, listen especially closely for fine microtonal gradations and shifts of timbre, which are often more important than clearly recognizable melodies. Work closely with other performers toward a shared, homogeneous sound image, since individual parts often represent only partials of a larger overall sound.