Sir Andr\u00E1s Schiff

“All the Keys Sounded Pure and Agreeable…”

Bach’s Well-Tempered Clavier

Richard Wigmore

The seeds of Bach’s most celebrated keyboard work— dubbed by conductor Hans von Bülow the “Old Testament,” to the “New Testament” of Beethoven’s sonatas— lie in the musical education of his eldest son, Wilhelm Friedemann. Johann Sebastian was as systematic in his teaching methods as in his compositions. In January 1720, while Kapellmeister to Prince Leopold of Anhalt-Köthen, he presented the nine-year-old Wilhelm Friedemann with a “little keyboard book” (Clavierbüchlein) into which he wrote pieces designed to hone technical skills and musical understanding. These include early versions of the Two- and Three-Part Inventions (or Sinfonias, as the latter were styled), some copied by Wilhelm Friedemann himself, and 11 of the first 12 preludes of what became Book I of The Well-Tempered Clavier.

By 1722 the 11 preludes, expanded and, in some cases, transposed into the more abstruse keys, had become 24 fully fledged preludes and fugues, arranged in chromatically ascending key sequence. The title page of Bach’s fair copy proclaims that the music’s purpose was both to instruct and delight: “The Well-Tempered Clavier, or Preludes and Fugues through all the tones and semitones… For the profit and use of musical youth desirous of learning and especially for the enjoyment of those already experienced…”

The first book of The Well-Tempered Clavier (Book II was only assembled in the early 1740s) duly became Bach’s prime teaching material, both for Wilhelm Friedemann and, later, Carl Philipp Emanuel, and for his more advanced pupils. Keyboard students learnt to read and play in all keys, across the widest possible gamut of idioms and textures. Bach’s composition pupils were able to study all the essential contrapuntal techniques in styles that ranged from the Palestrinainspired stile antico to the most fashionably up-to-date. Dozens of manuscript copies of The Well-Tempered Clavier remained in circulation in the decades after the composer’s death. Three separate editions published in 1801 and 1802 contributed crucially to the 19th-century Bach revival.

While Bach seems to have conceived the preludes and fugues primarily in terms of the harpsichord (though some work well on the organ), his use of the generic term “clavier” indicates that he wanted to make them available to players of any keyboard instrument—harpsichord, clavichord, organ, spinet. No one can be completely sure exactly what he meant by “well-tempered.” Scholars agree that it is unlikely to denote our modern temperament, with its 12 equalized semitones. One possible clue comes from Bach’s obituary, written by his second son Carl Philipp Emanuel and his pupil Johann Friedrich Agricola: “In the tuning of harpsichords he achieved so correct and so pure a temperament that all the keys sounded pure and agreeable. He knew no keys which, because of impure intonation, should be avoided.”

While ensuring that all 24 keys, even ones as outré as C-sharp major and D-sharp minor, were tolerable to the ear, Bach’s tuning system would have made some keys more “well-tempered” than others. The resulting differences of color and character, including a degree of harshness in the “extreme” keys of C-sharp and F-sharp major, with their relatively sharp major thirds, are inevitably lost in today’s equal temperament.

Bach’s was a famously encyclopedic nature. And Book I of The Well-Tempered Clavier, like its successor, is dazzling in its diversity, not only of style and technique but also of expressive scope. There is nothing dustily didactic about music that simultaneously challenges the mind and fingers, touches the heart and celebrates the joy of bodily motion. While the collection evolved over several years from a repertoire of teaching pieces, it is no accident that it begins with the simplest prelude in the purest, most innocent key—on to which Gounod grafted his syrupy Ave Maria—and ends with the longest and arguably most searching of the fugues, whose mingled grandeur and penitential awe evokes the opening Kyrie of the B-minor Mass.

Bach evidently conceived the preludes to showcase various types of keyboard texture. Several of those that originated in Wilhelm Friedemann’s Clavierbüchlein, including the preludes in C major, D major and D minor, elaborate a broken arpeggio pattern, in the manner of a Baroque lute improvisation. The preludes in C minor and B-flat major are coruscating moto perpetuo toccatas, tests of digital dexterity.

Throughout the collection, the lilt of the dance, grave or exuberant, is rarely far away. Some of the preludes, such as the ebullient, gigue-like F major and the luminous F-sharp major, are two-part inventions, while the G sharp–minor and B-major preludes could fit seamlessly into the book of three-part sinfonias. The E-major Prelude is a dulcet pastoral, the graceful A-major both a three-part invention and a miniature fugue. For the preludes in E-flat minor—a poignant sarabande—and E minor Bach writes an ornamental, Italianate arioso that could easily be transcribed for oboe or violin.

Bach is at his most galant in the irresistibly catchy A-flat Prelude, widely popularized in the gently swung version by the Swingle Singers. Conversely, the Prelude in E flat is an elaborate structure in three separate sections, with a quasiimprovisatory opening, a chorale-based fugato at its center and a closing fugue that combines the chorale with the improvisatory flourishes of the opening. You can sense Bach relishing the challenge of reconciling opposites here. After this cerebration, the E-flat Fugue—the lightest in Book I of The Well-Tempered Clavier—sounds like a witty jeu d’esprit.

Bach saves his most sublime preludes for the end of the collection: the B flat–minor, music of sorrowing tenderness that has been aptly likened to the opening chorus of the St. Matthew Passion, and the grave B-minor Prelude, with its chains of dissonant suspensions over a tramping bass line.

Beginning with the clear, calm unfolding of the C-major Fugue, the fugues in Book I of The Well-Tempered Clavier likewise explore a vast array of styles and methods with Bachian encyclopedic thoroughness. While most are in three or four parts, there are two in five parts—the grandly austere stile antico fugues in C-sharp minor and B-flat minor, that refract Renaissance polyphony through a Bachian prism. One of the fugues, the brilliant, toccata-like E-minor, is in just two parts, unfolding as a fugal two-part invention.

Throughout the collection Bach deploys every contrapuntal trick of the trade with consummate mastery, including stretto (with the fugal entries piling in on each other), inversion, and (in the ruminative Fugue in D-sharp minor) augmentation—the theme presented in longer note values. Most of the fugues have either one or two countersubjects. A few have none, while the chromatically contorted F-minor Fugue—which, like the B-minor Fugue, evokes the Kyrie of the B-minor Mass—has as many as three countersubjects. Perhaps the most contrapuntally rigorous of all is the vast, sternly archaic A-minor Fugue, which dwarfs its lively prelude. A pedal point at the end—the only such instance in the whole collection—suggests that Bach wrote this fugue either for pedal harpsichord or organ, perhaps in his early Weimar years.

The expressive spectrum is marked at one end by the mystic stile antico fugues in C-sharp minor and B-flat minor, where music, mathematics and philosophy commingle. In extreme contrast are galant fugues that dance and frolic. The G-major Fugue is a playful jig. Belying its “difficult” key, the modern­ sounding C sharp–major Fugue skips with impish grace. Similarly blithe are the fugues in F-sharp major, and triple-time fugue in B-flat major, with its brilliant, toccatalike figuration. In the G-minor Fugue, with its characteristically angular subject, the minor key even becomes a cue for quirky, cussed humor.

In the majestically rolling D-major Fugue—one of the most memorable of all—Bach evokes the pomp of a French Baroque overture. The Gallic spirit is felt elsewhere, too. The F-major Fugue is a Passepied, a livelier cousin of the minuet, while the A-flat Fugue has the elegant strut of a gavotte, completing the most immediately beguiling prelude-fugue pair in the whole collection.