Bach's Prelude in C major did not begin life as concert music — it began in a practice book. In January 1720 he started a keyboard notebook for his nine-year-old eldest son, and an early form of this piece is in it; two years later he revised it and placed it first in Book I of The Well-Tempered Clavier. The full piano score is on screen, note by note.
Nothing happens, and yet it keeps moving
There is no melody here. The hand opens and closes in one shape, over and over, with exactly the same distance between each turn — like walking down a row of evenly spaced columns, every step landing in the same place.
What changes is underneath. Each turn shifts the harmony one notch sideways, and you never catch the moment it moves; you look back after a while and the light is no longer the colour it was.
In the last few turns the lowest note sinks and does not come back up. The hand above keeps opening and closing while the floor beneath it has already stopped.
A hundred and thirty-one years later, someone sang over it
Bach's own fair copy of Book I of The Well-Tempered Clavier is dated 1722 on its title page, which also says the collection is for the use of young people who want to learn and for the pastime of those already skilled. The name refers to a matter of tuning: temper the instrument well enough and all twenty-four keys become playable. Exactly which tuning Bach had in mind has never been settled.
Then other people took the piece over. In 1853 Gounod laid a melody of his own over this prelude; his future father-in-law Zimmermann wrote it down and published it as Méditation sur le Premier Prélude de Piano de S. Bach. In 1859 it appeared with the Latin Ave Maria text, and from then on the melody on top was better known than the music underneath it.
One more thing, less widely known: from the early nineteenth century many editions carried an extra bar, inserted between bars 22 and 23. It appears in none of Bach's sources. It is generally credited to the Hamburg musician Schwencke — though even that is disputed, his own descendant having named his son instead. Urtext editions removed it long ago; ours is the thirty-five-bar version. The edition Gounod worked from was the one with the extra bar.
Thirty-two bars, one shape, sixty-four times
One low note, one in the middle, then three notes rising; those three come again, making eight. Eight to a group, two groups to a bar — and the two groups are note for note the same. The shape runs from the first bar to the thirty-second, sixty-four times, unchanged. The spacing never varies either: every note in the piece arrives one sixteenth after the last, with nowhere to draw breath.
Only the harmony travels. For the first nine bars the bass barely leaves the region of middle C; in bar ten it drops for the first time, then walks down a step at a time (G, F, E, D), dipping low and climbing back. From bar twenty-four the bass plants itself on one note and stays there for eight bars. Then it drops another octave to the lowest note in the piece — a note that does not appear until bar thirty-two, and once it does, it holds to the end.
The shape breaks for the first time in bar thirty-three: the right hand falls into the left hand's register, the staff switching to bass clef, and comes back only in the next bar — the widest bar in the piece, top to bottom. The last bar has no motion left in it at all, just one chord held down.
The hard part is not letting it speed up
Not one note here is hard to reach; the difficulty is the tempo. Every note is the same distance from the last, so half a note of hurry anywhere is audible — there is no melody to cover it, only one even line to be measured against.
The held bass note is the floor of each turn. Let the finger up early and the broken chord above it has nothing to stand on; it goes hollow.
In bar thirty-three the right hand drops into the left hand's register — the one place in the piece where the hands have to move past each other, and the next bar pulls them as far apart as they ever get.
We rate this 2 out of 5.
There are forty-seven more after this one
Same idea — one figure carried the whole way: Pachelbel's Canon, Satie's Gymnopédie No. 1.
What comes next: BWV 846 also has a fugue, which follows the prelude directly; Book I holds twenty-three more prelude-and-fugue pairs, forty-eight across both books.
The melody that was added later: Gounod's Ave Maria. Hearing it after the original, you notice the part underneath never changed.
