Sometimes when I’m practicing my current choir music, Bach’s Magnificat, I have to sit there and shake my head. At first, it was a case of “How on Earth am I going to do this?!” Over time, however, lots of time, I’ve arrived at a new question: “How on Earth did he do this?!”
So one day, armed with my own score and a pencil, I decided to try to figure out exactly what he was up to in those lines of music.
I think it’s highly appropriate that the first thing I saw as I opened to Omnes generationes was an instruction from my choir director that I had transcribed:
Breathe as needed. Observe rests.
I decided to tackle the most obvious component of this movement to see what Bach did. The entire piece consists of two words, “omnes generationes” [all the generations] repeated again and again. Bach brings this phrase in with five repeated eighth notes on the same pitch—a clarion trumpet call, announcing “all, all the generations.” It’s insistent.
You don’t have to read music to see this note pattern, it’s easy to pick out. Look, I’ll show you:
While the five-note theme is a trumpet, the voice in the “florid” section of notes is a stringed instrument. I picture a bow moving back and forth across the strings as the notes bounce up and down in my throat. Some nights I need a little more rosin.
But getting back to Bach, what does he do with this? Knowing I was only scratching the surface, I went through and circled the first note of all the instances of that five-note theme in each voice (Soprano 1, Soprano 2, Alto, Tenor, Bass).
He uses it 46 times in 27 measures.
He must mean it.
Then, I looked at what note in the scale of D major he used to start the phrase.
Answer: all of them
Except instead of G he used G#, and then he threw in B# (C natural) for good measure, so we have
D E F# G# A B B#/C C#
And this gets worked in with all the other notes swirling around it. Musical Sudoku at its finest.
And then, to make sure you didn’t miss the point, for effect he brings the phrase in, slightly offset in time, in each voice (it’s called stretto, Italian for tight or narrow, as in tightly packed voices).
“Did you miss it?” asks Johann. “If you did, I’ll make everybody come to a halt, and then bring in everyone together, then let the basses bring it home.”
And this is the easy phrase to explain.
And now I think it’s time to observe a rest. But first, let’s listen to Omnes generationes.
Bach, J. S., Magnificat in D BWV 243. Barenreiter 5103a vocal score. Vocal Score arranged by Eduard Müller, Edited by Alfred Dürr. Clifton, NJ, European American Music Distributors Corporation, 1956.
Link to scores online: http://imslp.org/wiki/Magnificat_in_D_major,_BWV_243_(Bach,_Johann_Sebastian)