Spain was a recurring source of inspiration for Maurice Ravel, whose mother was born there. Spanish colours and dance rhythms can be found in several of his works, but in Bolero from 1928 he distilled the idea in an almost radical fashion. Originally composed as ballet music, the work is based on the Spanish dance, the bolero.

The principle is as simple as it is ingenious. The snare drum maintains the same rhythm throughout almost the entire piece, while two melodies are repeated again and again. What changes above all are the sonority and dynamics. The melodies pass from one orchestral instrument to another, appearing in constantly shifting colours and combinations, while the music grows from a subdued opening to a tremendous crescendo.

Ravel himself described Bolero as an experiment in orchestration. Throughout the long build-up, the music seems almost to stand still while remaining in constant motion. Only towards the very end is the hypnotic pattern broken by a surprising change of key. After so much repetition, the effect is all the more striking – and quickly propels the music towards its explosive conclusion.