← Bach · Well-Tempered Clavier
Prelude 15 in G major BWV 860
Book I of the Well-Tempered Clavier. Under its figuration, this prelude is 20 chord changes across 19 bars — ranked 3 of 42 by measured difficulty (intermediate) in this survey. Played as block chords, it's a progression you can learn in an afternoon; the piece is that progression wearing sixteenth notes.
Practice this piece → Practice chords → Learn it section by section → Hear the harmony →
How it opens
The first changes are vi7 (G) · I7 · V7/V (G) · iii7 · V7/V (E) · V7 · viio7/ii · ii — and the whole prelude keeps moving at roughly that harmonic pace.
What it leans on
Of 20 labeled changes, the harmonies that do the most work: V7 (3×), vi7 (G) (2×), I7 (2×), V7/V (E) (2×), V7/V (G) (1×).
Free scores
- Blocked-chord reduction (MusicXML) — the harmony skeleton the player performs
- The prelude as written (MusicXML)