← Bach · Well-Tempered Clavier
Prelude 20 in A minor BWV 889
Book II of the Well-Tempered Clavier. Under its figuration, this prelude is 105 chord changes across 33 bars — ranked 33 of 42 by measured difficulty (expert) 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 viiø7/VII (E) · iv7 (A) · V7 (G#) · VI · V7 (D) · VI7 (C) · V7 (B) · VI (A) — and the whole prelude keeps moving at roughly that harmonic pace.
What it leans on
Of 104 labeled changes, the harmonies that do the most work: III (E) (5×), ii (A) (5×), iv7 (A) (3×), V7 (G#) (3×), V7 (D) (3×).
Free scores
- Blocked-chord reduction (MusicXML) — the harmony skeleton the player performs
- The prelude as written (MusicXML)