The Well-Tempered Clavier, Book 1

The Well-Tempered Clavier, BWV 846–893, consists of two sets of preludes and fugues in all 24 major and minor keys for keyboard by Johann Sebastian Bach. In the composer's time clavier referred to a variety of keyboard instruments, namely the harpsichord, the clavichord and the organ (which operates using air instead of strings), but not the regal and the then newly-invented pianoforte.

Composition history

Each set contains 24 pairs of prelude and fugue. The first pair is in C major, the second in C minor, the third in C♯ major, the fourth in C♯ minor, and so on. The rising chromatic pattern continues until every key has been represented, finishing with a B minor fugue. The first set was compiled in 1722 during Bach's appointment in Köthen, and the second followed 20 years later in 1742 while he was in Leipzig.

Bach recycled some of the preludes and fugues from earlier sources: the 1720 Klavierbüchlein für Wilhelm Friedemann Bach, for instance, contains versions of eleven of the preludes of the first book of the Well-Tempered Clavier.

Content

Each Prelude is followed by a Fugue in the same key. In each book the first Prelude and Fugue is in C major, followed by a Prelude and Fugue in its parallel minor key (C minor). Then all keys, each major key followed by its parallel minor key, are followed through, each time moving up a half tone: C → C♯ → D → E♭ → E → F → F♯ → ... ending with ... → B♭ → B.

Style

Musically, the structural regularities of the Well-Tempered Clavier encompass a wide range of styles. The preludes are formally free, although many of them exhibit typical Baroque melodic forms, often coupled to an extended free coda (e.g. Book 1 preludes in C minor, D major, and B♭ major). The preludes are also notable for their odd or irregular numbers of measures, in terms of both the phrases and the total number of measures in a given prelude.

Each fugue is marked with the number of voices, from two to five. Most are three- and four-voiced fugues, but two are five-voiced (the fugues in C♯ minor and B♭ minor from Book 1) and one is two-voiced (the fugue in E minor from Book 1). The fugues employ a full range of contrapuntal devices (fugal exposition, thematic inversion, stretto, etc.), but are generally more compact than Bach's fugues for organ.

Several attempts have been made to analyse the motivic connections between each prelude and fugue – most notably Wilhelm Werker and Johann Nepomuk David. The most direct motivic reference appears in the B major set from Book 1, in which the fugue subject uses the first four notes of the prelude, in the same metric position but at half speed.

Music

In November 2013 Ishizaka and Open Goldberg Project completed another Kickstarter project to fund the recording Book I of Bach's Well-Tempered Clavier. The new recording was released into the public domain in March 2015.

In Gramophone, Donald Rosenberg wrote, "She scales her Bach to the rhythmic, structural and sonic needs of the music, without touching the sustaining pedal."

James Oestreich, reviewing for The New York Times, reported that Ishizaka is a "gifted and obviously devoted Bachian" and that she "performed the 24 preludes and fugues of Book 1 from memory and without major flaw".