This prelude is something of an enigma. Its sectional form revertsto the type of organ prelude that Bach had cultivated in his youth, but had aban- doned in his later Weimar days in favour of the large-scale piece in a single span, using the principles of the Venetian concerto allegro. The key of E flat is missing from the sequence of preludes in the Clavier-Büchlein, which has led to specula- tion that this is an old piece which Bach kept in reserve and did not include there, probably because it was too long and difficult for the ten- to twelve-year- old Wilhelm Friedemann. It also does not fit in the keyboard-technical scheme of the other Clavier-Büchlein preludes, and it is unique among preludes in the 48 in including a fully developed fugue. It may originally have been conceived for organ (the early version has fewer semiquavers in the bass of the second section (bb.10–24) than the final one), in which case the key of E flat might seem to indicate that it could not be an early work. Mattheson (1719) said he knew of no toccatas or preludes in ‘that fine, majestic key’ because of the tuning of organs.62Nonetheless, in Bach’s area there are organ pieces in E flat dating from
his youth, by Johann Pachelbel (1653–1706), and in the so-called ‘Mylau tabla- ture’ (compiled 1689–1700). He himself wrote for organ in E flat in the early layer of chorale preludes in the Orgel-Büchlein (‘O Mensch bewein’, see Stinson 1996 p.29). With its sophisticated French harmony, glorious spacing, and density of contrapuntal argument, the E flat prelude cannot be as early as the clavier toccatas. None of the early sectional preludes/toccatas is as integrated as this, and they tend to revert to the free style at the end.63
Bach may have composed it specially for The Well-tempered Clavier to repre- sent one type of prelude: the sectional organ praeludium, with subtle thematic links between sections, as cultivated at its most sophisticated by Buxtehude (see Chapter Three section 3). It is nonetheless such a large and impressive concert item in itself, without the obvious didactic keyboard-technical function of the other preludes so far, that it may perhaps be more likely to have originated as a free-standing virtuoso piece in Weimar after around 1710. It certainly chimes in with the general policy of the collection in giving its elements a highly inte- grated treatment, and it may be seen as a step on the way from the early sectional preludes and toccatas to the more seamless integration of prelude and fugue elements in the C minor organ Praeludium BWV 546/1, dating from after Bach’s arrival in Leipzig in 1723.
The E flat prelude is typical of Bach’s maturity in creating a union of oppo- sites. The opening uses an improvisation hand-shape figure, suitable for the feel (‘Griffe’) of the key, and developed over a pedal point. Although it is in the style of a free improvisation, it is not difficult to see the underlying pattern of rising 4ths and 5ths which provide the material for the next, strictly contra- puntal, section (from b.10). This fundamental unity is emphasised by an instruction pencilled in (not by Bach) to the autograph at b.10: ‘not like an Alla breve, but continued as in the first bar’.64In other words, the player is not to imagine the time signature changing to and the tempo doubling, to what one might think suitable for the E flat fugue of Book II. It shows that this section was thought of as in stile antico, which it certainly is in its ‘gebunden’ (prepared and resolved) treatment of dissonance, and fluid metre. It is nonetheless a special effect, designed to contrast with the first section, and is untypical of true
stile antico in being a solid, sustained block of counterpoint with no rests after
the voices have entered. Bach made few alterations to the final version of this prelude, other than adding two bars to the first section (bb.3–4) and the deco- rative semiquavers in bb.20–1. The bass decoration in b.22 was originally in demisemiquavers. By converting it to semiquavers, and having it move down the parts in pitch, Bach makes this ornament quasi-thematic, brings out the glorious 9/7 chord at b.23, and links the 4th and 5th leaps of the second section to the semiquaver subject of the third.
Section 3 is a masterly double fugue in counterpoint at the octave, 10th and 12th which is yet a model of clarity and playability since it is based on the four-
note handshape of Section 1. Inversions at the 12th are in b.47f (compare b.25) and b.49f; at the 10th in b.53f. The semiquaver subject also includes the emphatic repeated notes used in Subject 3 of the C sharp minor fugue for building up the final climax, and which here subtly prepare the cathartic bass entry at b.61.
After such an imposing fugal creation, what can one possibly addunder the heading of Fugue? Busoni’s dreadful idea of following it with the E flat fugue from Book II, a less imposing piece in the same vein, only serves to emphasise the quality of Bach’s artistic judgment and especially his demonstra- tion that the genre of fugue is as capable of as great a range of style and expres- sion as any other, except that it has an added dimension of intellectual delight rarely to be found in, for example, the operatic aria. This fugue contrasts strongly with its prelude in its much lighter style, with violin-sonata figurations and passages of what are in effect embroidered continuo harmony. Yet there are so many subtle allusions to the materials of the prelude that can hardly be accidental that the fugue seems designed to show how opposite expressions may derive from the same materials; or, in line with the policy of updating traditional techniques, that traditional solemn ingredients can be treated in a light and ‘modern’ way.
The subject in itself unites the E flat hand-shape of the opening of the prelude with the outline of the stile antico subject of the double fugue. It expands the hand from a 5th, to a 6th, to a 7th just as the prelude figure expanded it from a 5th to a 7th; and the relationship to the stile antico subject at b.25 of the prelude is clear from the answer in b.3 of the fugue (outlining b
♭
e'♭
d' g' f'). However, this underlying stile antico outline is reinterpreted in a ‘modern’ tonal subject which modulates to the dominant. Modern too is the fact that the argument of the fugue is hardly contrapuntal (there is double, but not triple counterpoint), but harmonic in that it takes the chromatic step inherent in the subject and its continuation (a'♮
in b.1, a'♭
in b.2) as the principal point of interest, extends it in the linking passage at bb.4–5, and motivates such touches as the chromatic step in the countersubject at the beginning of b.6, which replaces what would otherwise be an octave leap (– d'–d"). The growth of this element, in the context of such a light style, into sequences of such richly chromatic and dissonant chords as in bb.14–16 is one of the principal delights of this fugue. Its relation to the prelude is made clear by the chromatic falling line in the Schumannesque final bar, recalling the corresponding chromatic line between cantus and alto in the last three bars of the prelude.The fact that the subject modulates may explain the simplicity of the general harmonic plan. It is another version of the combination of fugue and binary sonata observed in previous fugues. In this case almost all of the first half (to