Prelude & Fugue No. 15 in G Major

The Prelude in G Major initially appears one of Bach’s flash-in-the-pan, one-minute wonders: all sparkle and no substance. That is, until you listen to it for the second time. What appear to be fairly standard patterns of splayed-out chords and scale passages in the first half of the piece, become gloriously expressive phrases—falling then rising—in the second half. Because Bach’s notation suggests this is to be played at a helter-skelter speed, the beauties of the music pass in a blur and we want to go back and listen again almost immediately. This was surely deliberate. This scamper of a Prelude is an excellent warm-up act for the long-breathed fugue which follows. The theme on which it is based contains written-out ornaments (turns) which inspired much of the surrounding music. Bach is playfully academic with the main theme, soon turning it upside down and then shortening it by a bar. But the movement remains spacious and graceful to the end. About J.S. Bach’s Well-Tempered Clavier Book I If we had to choose the most influential of Bach’s works in the centuries since his death, the biggest votes would probably go to the St Matthew Passion and The Well-Tempered Clavier. The epithet “well-tempered” refers to “equal temperament”—a new method of tuning keyboard instruments, which made a wide range of keys available. Bach showed off these possibilities in two books of preludes and fugues in all 24 major and minor keys, which is why the collection is sometimes known as the “48”. Partly drawing on earlier works, Bach completed Book 1 around 1722, and Book 2 20 years later, constantly revising both. He intended the pieces to be useful to players of all types of keyboard instrument.