What actually is a prelude, and why are preludes so often grouped in series of two dozen? The first one to have the idea of using all twelve notes of the chromatic scale, i.e., each one in the major and minor keys, was Johann Sebastian Bach. Before him, it was not even possible, due to unequal temperament. Bach’s cycle of preludes a fugues, The Well-tempered Clavier, which alternates all the major and minor keys, was regarded as a foundation stone to instructive piano literature, and became a model for subsequent generations of composers. In his turn, Frédéric Chopin (1810-1849) approached preludes as a free form: while some of his works in this genre consist of a mere handful of bars, others are larger-scale; some are minutiously detailed miniatures, others tackle elaborate motifs; some are built around melody, others rely on virtuoso passages. Chopin was completing this particular series in Mallorca, distressed by disease, the climate, and the peripeties of his relationship with the author, George Sand. In fact, two of the preludes, Nos. 4 and 6, were performed at Chopin’s funeral.

Dmitri Shostakovich went still further in imitating Bach’s model in his series of 24 Preludes, Op. 34 (1933), and again in 24 Preludes and Fugues, Op. 87 (1951). Anyway, regardless of these works’ occasionally rough-hewn modernist expression, it is indeed possible to trace down even there echoes of influence by Chopin. The consummate pianist that he was himself, Shostakovich was very well acquainted with Chopin’s music (incidentally, he took part in the first edition of the Chopin Competition, in 1927, though he did not make it to the top three).