The
prelude is 35 bars long and consists mostly of
broken chords. Below are the first four bars of the prelude:
The prelude continues like this with different variations on harmony and
change of key. The prelude ends with a single C major chord.
Fugue
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adding to it. (October 2017)
The
fugue is 27 bars long and is written for
four voices. It starts with a two-measure
subject in the alto voice. The first voice to join is the soprano, which replies with the answer in the dominant key (G major).
The answer is repeated in the tenor and bass voices when they enter. The piece then
modulates through various
related keys, with the subject being repeated in each of the four voices. The piece eventually ends up back in the home key. It ends with each voice stopping at a note and holding it until the end, forming a C-major chord.
Legacy
Schwencke measure
Some earlier editions of the prelude contain an extra
bar between bars 22 and 23 known as the "Schwencke measure", a measure allegedly added by
Christian Friedrich Gottlieb Schwencke in an attempt to correct what he or someone else erroneously deemed a "faulty" progression (though it may be accidentally corrupted manuscript(s) associated with Schwencke), even though this sort of progression was standard in the music of Bach's time.[1]
However, according to
Hermann Keller, "Schwencke was a sophisticated and well-informed musician who was probably not thinking of improving Bach."[2]
Arvo Pärt's
"Credo" is built around Bach's C major prelude, first unravelling it through the central cacophonous
twelve-tone part of the work, then remerging on the piano with the chorus and orchestra joining in harmony for the massive finale.
Mstislav Rostropovich compared this Prelude to the introductory bars of the prelude of Bach's
Cello Suite No. 1, in a video named Rostropovich interprets Bach, filmed in 1991 at the Basilique Sainte Madeleine in
Vézelay, France.
^
abcBarber, Elinore (1970). "Questions to the editor". Bach. 1 (1): 19–22.
JSTOR41639775. The insertion of the measure shows a fundamental misunderstanding of Bach's skip in the bass from F-sharp to A-flat. It seems unlikely that any knowledgeable contemporary of Bach's would have tried to 'correct' this not uncommon bass progression.
^Rothfarb, Lee Allen (2009). August Halm: A Critical and Creative Life in Music. University of Rochester Press. p. 56.
ISBN9781580463294.
^Lockwood, Lewis; Webster, James; Reynolds, Christopher; eds. (1996). Beethoven Forum, p. 70. University of Nebraska.
ISBN9780803229211. Halm (1905). "Musikalische Logik", Der Kunstwart 18, pp. 486-487.