# Bach's choices in the chromatic ascent cross-over in the two WTC books



## nobilmente

In the WTC-I #8, Bach has the prelude in Eb minor, and the fugue in D# minor. In the corresponding WTC-II, both prelude and fugue are in D# minor. Any views on his motivations here?

I think the Book I fugue is amazing, however when sight-reading it would be easier in D minor I think, the proliferation of double-sharps is rather intimidating...


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## millionrainbows

In WIK, under *"D-sharp minor,"* the foibles of this key are discussed. The problems come in when using alterations of the natural minor scale, which are the D# harmonic minor scale and melodic minor. In both, the seventh scale tone (leading tone) must be C-double sharp.

In *Eb minor, *these double-sharps would be written a naturals. Is that easier for you?

In the 24 canonic keys, *most composers prefer E-flat minor,* *while Bach, Lyapunov, and Ponce preferred D-sharp minor.*

From Bach's Das Wohltemperierte Klavier, the eighth fugue from Book 1 and the eighth prelude and fugue from Book 2 are in D-sharp minor; both fugues end with a Picardy third, requiring an *F







* in the final D-sharp major chord.


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## drmdjones

Since Ponce was mentioned, here's a little side note. In his 24 preludes for guitar he moves around the circle of fifths pairing relative keys: C Am G Em etc. His last pair are in one flat. So we find F major but instead of Dm he uses A phrygian. Very cool I think.


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## nobilmente

Richard Atkinson has done an excellent analysis of the piece originally mentioned:





Regarding other works in the somewhat exotic key, mention should go to Scriabin's splendid etude:


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## Schoenberg

Try playing the WTC I prelude in D# minor, or the fugue in Eb minor, it will become apparent why he chose those keys.
You could most likely do the same with the WTC II prelude and fugue and obtain similar results, though I have not studied these works so I wouldn't know for certain.


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