Performance Record of J.S. Bach – WTC I No. 2 Prelude and Fugue in C Minor, BWV 847

Overview: A performance of J. S. Bach’s The Well-Tempered Clavier, Book I, No. 2 — Prelude and Fugue in C Minor (BWV 847). The performer reflects on the special consonance of the final chord, contrasts pure just intonation with 12-TET, and traces energy-shaping devices across the fugue.

Note: All content on this page is originally explained by Reiji in Japanese. The English version is translated by AI and structured by a parent, with Reiji's final approval.

Reiji's Words and Ideas

• Performer’s Comment — The final chord:
  For me, the final chord of the fugue is the single most consonant sonority in the entire piece. If we think of this chord in pure just intonation, the fundamental (8′), second partial (4′), third partial (3/2′), fourth partial (2′), and fifth partial (5/3′) all line up beautifully. In 12-tone equal temperament, the tone corresponding to the third partial is about 1.96 cents flat, and the tone corresponding to the fifth partial is about 13.69 cents sharp. There is a small discrepancy, but even so, this chord sounds more consonant here than in most other places.
• Teleology — Moving toward the last consonance:
  Throughout the prelude and fugue there are several local points of resolution, but the consonance of the final chord stands out in a special way. Because of this, I came to feel that the whole piece, prelude and fugue together, is moving toward this final consonance.
• Energy devices in the fugue:
  In this work, I sense many devices that keep pushing the musical energy forward. For example, in the fugue there are two passages where the same motive ascends step by step. The first appears in bars 17–18, and the second in bars 19–21. The same motive rises higher and higher, and the energy reaches its peak around bar 20. From bar 21, that accumulated energy changes direction, as if it were turning into downward motion, and from bar 22 the harmony suddenly begins to move rapidly:
  Cm → Fm → B♭ → E♭ → A♭ → Ddim7 → G7
• Silence as zero gravity:
  Later, in bar 28, all voices rest and the music falls silent for a brief moment. To me, this silence feels like a moment when gravity drops to zero and the music is flying through the air, trying to reach “something not yet attained.” From there, it finally lands on the last chord, whose consonance feels overwhelmingly complete to me.
• *These are, of course, only my personal impressions as a performer.