J. S. Bach : Prelude no. 1 from Book 1

This is the first and best known prelude from Bach's 48 Preludes and Fugues, known as the Well-Tempered Clavier. It was used by Gounod for his famous Ave Maria adding a tune above Bach's harmonies. A must for any serious student of piano, Book 1 and Book 2 are available from Sheet Music Plus.