Bach: Prelude and Fugue No.3 in C♯ major, BWV 872 Analysis

Analysis

Prelude

Bach Prelude and Fugue No.3 in C# Major BWV 872 Analysis 1

SUMMARY:

This Prelude is built upon the characteristic figure seen above, which is used twice in every bar, until the Fugato (3/8).

Bars 1-6: Period I. Ending with a Perfect Cadence in the key of the Dominant.

Bars 6-20: Period II. Starting in G sharp major, it modulates to D sharp minor (Bar 7), then to the Relative minor (A sharp) (Bar 8). From here it works very gradually onwards, touching its Subdominant (F sharp), then D sharp minor, G sharp major, the F sharp major (Bars 12-16), before ending with a Perfect Cadence in the key of the Tonic, C sharp.

Bars 20-25: Short Modulatory Passage. Ending with a Perfect Cadence on the Dominant, G sharp, leading to the Fugato (3/8).

Bars 25-50: Fugato (3/8) in three parts. Staring in G sharp, it points to the Tonic key, and momentarily lands there by a Perfect Cadence in Bar 34. Then it gradually moves to its Dominant (G sharp) for the moment (Bars 35-40), and passing gradually through A sharp and D sharp minors (Bars 44-45), it works its way back to the Original key.

REMARKS:

Period II is capable of subdivision at Bar 13, where there is a Perfect Cadence in the key of the Subdominant.

The Short Fugato, which is written with a certain amount of freedom, contains two great centres to rest the mind upon momentarily, and to settle firmly the harmonic basis; (1) at Bar 34, where there is a Perfect Cadence in the Tonic (C sharp), and (2) at Bar 41, where there is a Perfect Cadence in the Dominant (G sharp).

This Prelude affords another notable example of the practice very much in vogue in the days of Bach and Handel, of Preludizing by the employment of a carefully selected series of chords forming a substratum for ornamental work containing beautiful and varied forms to be planted upon (See Preludes 1, 3, 5, and 6, Book 1). In the present instance the ornamental arpeggio work is not carried through to the very end of the movement, but a short Fugato in a different tempo (3/8) is added, taking the place of a Coda, and with this the movement winds up. Thus an additional element very happy in the interests of variety is secured, and the beauty of the whole greatly enhanced.

 

Fugue

Bach Prelude and Fugue No.3 in C# Major BWV 872 Analysis 2

ANALYSIS:

ENUNCATION SECTION:

Bar 1: Subject in Bass [C sharp major].
Bars 1-2: Answer in Treble. No Counter-subject [G sharp major].
Bar 2: Subject in Alto by Inversion [C sharp major].
Bars 3-4: Codetta [C sharp major].
Bar 4: Subject in Treble [C sharp major].
Bars 4-5: Answer in Alto [C sharp major].
Bar 5: Subject in Bass [C sharp major].
Bar 5: Subject in Treble by Diminution [G sharp major].
Bars 5-6: Answer in Alto by Diminution [D sharp minor].
Bar 6: Subject in Bass by Diminution and Inversion [A sharp minor].
Bars 6-7: Codetta, modulating from A sharp minor to G sharp major.
Bar 7: Subject in Bass [G sharp major].
Bars 7-8: Answer in Alto [G sharp major].
Bar 8: Answer in Treble [F sharp major].
Bar 9: Stretto I. Subject in Bass by Inversion [D sharp minor].
Bars 9-10: Subject in Alto by Inversion [D sharp minor].
Bars 9-10: Answer in Treble [G sharp major].
Bars 10-11: Stretto II, Subject in Bass by Inversion [C sharp major].
Bar 11: Subject in Treble by Inversion [C sharp major].
Bar 11: Answer in Alto [C sharp major].
Bars 11-12: Subject in Bass [F sharp major].

MODULATORY SECTION:

Bars 12-14: Episode I, modulating from F sharp through A sharp to E sharp major.
Bars 14-15: Stretto III, Subject in Bass [A sharp minor].
Bars 14-15: Subject in Treble by Inversion [A sharp minor].
Bar 15: Answer in Alto [D sharp minor].
Bars 15-16: Subject in Treble by Inversion [G sharp major].
Bars 16-17: Codetta, modulating from G sharp to C sharp.
Bar 17: Subject in Bass [C sharp major].
Bars 18-19: Subject in Alto by Inversion and Diminution [C sharp major].
Bar 19: Subject in Bass by Inversion and Diminution [D sharp minor].
Bars 19-20: Subject in Bass by Diminution [F sharp major].
Bars 20-24: Episode II, modulating from F sharp through C sharp, and back to F sharp.
Bar 24: Answer in Bass [C sharp major].
Bar 25: Stretto IV, Subject in Treble by Inversion [C sharp major].
Bars 25-26: Answer in Alto by Augmentation [F sharp major].
Bars 25-26: Answer in Bass [D sharp minor].
Bars 26-27: Codetta.
Bars 27-28: Answer in Bass by Augmentation [C sharp minor].
Bar 28: Subject in Treble by Inversion on Dominant of C sharp [C sharp minor].
Bars 28-29: Answer in Treble [C sharp minor].
Bar 29: Answer in Alto (varied) [C sharp minor].
Bar 30: Subject in Alto by Inversion (varied) [D sharp minor].

RECAPITULATORY SECTION:

Bars 30-31: Subject in Alto by Inversion (varied) [C sharp major].
Bars 31-32: Answer in Bass [C sharp major].
Bars 32-33: Florid passages in five parts.
Bars 33-35: Coda [C sharp major].

SUMMARY:

Exposition: Bars 1-7.
Counter-exposition: Bars 7-12.
Counter-subject: None.
Episodes: Two.
Stretti: Four.
Codettas: Four.
Dominant Pedal: Bars 28-30.
Tonic Pedal and Coda: Bars 33-35.

REMARKS:

  1. This Fugue has a “tonal” Answer, and would be called a “tonal” Fugue. The alteration in the Answer, for the sake of tonality, is made from the third note to the fourth.
  2. The Subject of this Fugue is the shortest in the whole work and consists of four quavers (eighth notes) only. At a first glance it might be thought to consist of thirteen notes, but it is almost immediately obvious that only the first four are employed, as a rule, for future employment.
  3. The device of Inversion is employed very early in this Fugue (Bar 2, Alto part).
  4. Diminution is used as early as Bar 5, and Augmentation is used on two occasions (Bars 25 and 27).
  5. In the Stretti, Inversion is always present, and in the last (no IV) Augmentation also.
  6. There is no Stretti in Bars 4-6, because in every case the Answer enters after the conclusion of the Subject.
  7. Episode I (Bar 12) contains in the Bass part reminiscence of the Subject by Inversion; the two upper parts are formed from new figures working in a descending sequence.
  8. Episode II (Bar 20) is much the same in construction as Episode I.