

Ep. 102: Bach's Most Famous Prelude (& Fugue...) BWV 846
In the beginning was the arpeggio, and the arpeggio was in C major, and the arpeggio was C major…
To which ill-tempered friend will you send this?
We are lucky Bach bothered writing out his arpeggio preludes. Here, for example, is what would later become the C-sharp Major prelude, from Book 2:
Who, without the aid of Bach’s revisions, would be so bold to turn that into:
So too, in the early versions of the opening of the Well-Tempered Clavier, Bach loses little time writing out the figures. He even stops writing half-notes toward the end:
Only 24 bars in its conception! A further revision in W.F.’s notebook sees a 28 bar version of the piece— the fair copy of 1722 is 35 bars (not 36! Listen for my discussion of the Schwencke measure.)
Some other pieces in this style:
The fugue also underwent revisions, especially to its theme. Layers A1 and A2 have:
Landowska recorded this version and wrote program notes about her decision (heard in the episode.) The 32nd notes of the subject were added in the third ‘layering’. Finally, Bach makes the finest revision in A4— in the 1740s(!), changing the bass in bar 15:
to this:
Finer and finer. Curvier and curvier. The image of Bach in the workshop with the chisel is a fascinating one.
Links mentioned:
The earlier episode covering this prelude (inverting it chromatically and other fun tricks)
Regarding the 2nd note each arpeggio in the earliest version of the prelude, see Legato playing and hidden polyphony on the harpsichord (Thanks to Erzdorf for sharing this, highly recommended.)
And, as mentioned in the episode, Wanda with Leo Tolstoy:
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Concepts Covered:
We discuss the prelude as a possible invitation to check the new system tuning, the famous pieces of Bach, and the Minuet in G being not by Bach but by Petzold. Explore the evolution and historical significance of Bach’s Well-Tempered Clavier, a landmark in keyboard literature and tuning theory. This episode traces Bach’s compositional development of key preludes and fugues, such as the C-sharp Major Prelude (Book II) and the C Major Prelude (Book I), BWV 846 analysis, revealing how Bach expanded brief sketches—some only 24 bars—into fully realized works through meticulous revisions. The Schwencke measure- his mistake. Discussions of simplifying Bach, also we examine counterpoint in detail, including changes to fugue subjects, rhythmic diminution, and voice leading, with examples from layers A1–A4. The discussion includes the function of the preludes as tools to demonstrate well-tempered tuning, their pedagogical role, and Bach’s workshop-like revision process. Also covered: authorship controversies, authentic Bach, such as the Minuet in G, long attributed to Bach but now credited to Christian Petzold. An in-depth look at how Bach's compositional process shaped one of the most enduring works in Western music.
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