Bach: WTC I, Prelude in E flat minor, Fugue in D# minor

When you are this far out on the circle of fifths it is moot whether you use six flats or six sharps so Bach gives us one of each. D# minor is the enharmonic equivalent of E flat minor, that is, they are the same, but spelled differently. Like fish or phish.

The prelude is a lovely piece that is both a sarabande and an aria, first for soprano and later for bass. There is not too much more to say about it unless we analyze the harmonies in detail. I'm not going to do that, except to say that Bach, as always, shows his great command of harmony, here to create some piercing dissonances that resolve beautifully.

The fugue is a whole other kettle of fish, however! Here Bach really shows all the possibilities of the subject:

 The fugue is in three voices and we hear this subject first in the alto, then the soprano, and finally the bass. Then there is an episode with some lovely chromatic passages. Next we hear the subject in stretto with the soprano following the alto one half-note later. After another short episode we hear the subject inverted:

We hear this first in the soprano, then in the alto, and after another short episode, finally in the bass. After another episode we hear the original subject in stretto with the soprano following the bass after a half-note. Then we hear the inversion in stretto with the alto following the bass at a half-note. There is another entry of the inversion in the soprano then Bach presents the subject, in the bass, in augmentation, with doubled note values:

The subject in augmentation appears twice more, once in the alto and finally in the soprano and another brief episode takes us to the cadence. Let me see, did Bach leave anything out? The subject in augmentation in stretto is all I can think of! Maybe later on in the Well-Tempered Clavier.

We are a very long way from the simplicity of the first prelude and fugue in C major.

UPDATE: I forgot to include a performance. Here is a fine one by Sviatoslav Richter: