# The C minor Prelude, harmony only (after Bach, BWV 847)

**Composer of this Composition:** Peter · **License out:** CC BY-SA 4.0
**Meter:** 4/4 · **Tempo:** quarter note ≈ 80 BPM; at bar 28, 120 BPM; at bar 34, 40 BPM; at bar 35, 96 BPM · **Length:** 38 bars
**Directionality:** 0.3 (stay close to the chords; textures are welcome if the harmony is right)
**Allowed transforms:** trim, gain, fade (no pitch-shift, no time-stretch)

## Prose

Where the C major glows, this one runs: a machine that won't stop, restless and driving. One chord per
bar, on the downbeat. The bass walks down into E-flat major (bars 11–14), the brief bright room.
Diminished sevenths pull it back. A C pedal holds bars 1–4. The long G pedal (bars 21–29) piles up the
tension, then it breaks loose and ends in light.

At bar 28, 120 BPM, Presto. At bar 34, 40 BPM, one held C7. At bar 35, 96 BPM, through the last bar.
Bars 35–37 sit on a C pedal. The last chord is C major, held and ringing.

Close and dry for the running part, and let the final chord bloom.

## Chord anchors (one per bar)

| Bar | Chord | Bar | Chord | Bar | Chord |
|---|---|---|---|---|---|
| 1 | Cm | 2 | Fm/C | 3 | Bdim7/C |
| 4 | Cm | 5 | Ab/C | 6 | D7/C |
| 7 | Gm/Bb | 8 | C7/Bb | 9 | Fm/Ab |
| 10 | Bb7/Ab | 11 | Eb/G | 12 | Abmaj7/C |
| 13 | Bb7/D | 14 | Eb | 15 | F7/Eb |
| 16 | Bdim7/D | 17 | Bdim7/C | 18 | Cm7/Bb |
| 19 | Fm7/Ab | 20 | F#dim7/A | 21 | Cm/G |
| 22 | F#dim7/G | 23 | Cm/G | 24 | Abmaj7/G |
| 25 | G7b9 | 26 | Abmaj7/G | 27 | F#dim7/G |
| 28 | Am7b5/G | 29 | F#dim7/G | 30 | G7/F |
| 31 | Cm/Eb | 32 | Cm | 33 | Ddim/F |
| 34 | C7 (held) | 35 | Bdim7/C | 36 | Edim7 |
| 37 | C7 | 38 | C (held, ringing) |  |  |

Slash chords name the bass. A Performer that can't match a bass note may let it go, but it should keep the chord.

## Composition

*Structure:* `4/4 · 80 BPM · at bar 28, 120 BPM · at bar 34, 40 BPM · at bar 35, 96 BPM · [1 bar Cm][1 bar Fm/C][1 bar Bdim7/C][1 bar Cm][1 bar Ab/C][1 bar D7/C][1 bar Gm/Bb][1 bar C7/Bb][1 bar Fm/Ab][1 bar Bb7/Ab][1 bar Eb/G][1 bar Abmaj7/C][1 bar Bb7/D][1 bar Eb][1 bar F7/Eb][1 bar Bdim7/D][1 bar Bdim7/C][1 bar Cm7/Bb][1 bar Fm7/Ab][1 bar F#dim7/A][1 bar Cm/G][1 bar F#dim7/G][1 bar Cm/G][1 bar Abmaj7/G][1 bar G7b9][1 bar Abmaj7/G][1 bar F#dim7/G][1 bar Am7b5/G][1 bar F#dim7/G][1 bar G7/F][1 bar Cm/Eb][1 bar Cm][1 bar Ddim/F][1 bar C7][1 bar Bdim7/C][1 bar Edim7][1 bar C7][1 bar C]`

## Credits

- **Music:** Johann Sebastian Bach, public domain. Prelude from *Das Wohltemperierte Klavier* I (1722).
- **Harmony:** Mark Gotham et al., *When in Rome*, CC BY-SA 4.0, commit 1c61fe4,
  https://github.com/MarkGotham/When-in-Rome, `Corpus/Keyboard_Other/Bach,_Johann_Sebastian/The_Well-Tempered_Clavier_I/02/analysis.txt`.
  The Roman numerals were converted to absolute chord symbols, so this harmony is an adaptation and is shared alike.