Sarah was ninety years old

In the course of listening to all the music in my iTunes library at least twice (a multi-year project!), this morning I came across Arvo Pärt’s 1991 album Miserere. It’s a touchpoint for me—it was the first album of his music I ever bought, probably the first Hilliard Ensemble album I ever got, and one of the first albums of modern classical music I ever bought. (I think the first modern classical album I bought was the Kronos Quartet’s Black Angels.)

As I listened to it, I remember being simultaneously profoundly moved and confused by the third track, “Sarah was ninety years old,” scored for three voices, percussion, and organ. The piece begins in contemplative solo percussion, which gradually picks up intensity until the first vocal entrance, then repeats, until finally the long stretches are ended by the entrance of an organ and a soprano solo that spirals up into ecstasy (as Sarah conceives and bears a son at the age of 90).

Something that had puzzled me from my first listen was just exactly how it was that the percussion didn’t drive me nuts. The percussion consists of four-beat patterns of high and low tones, continuing initially for over five minutes before voices enter. How does it pull the listener in?

I think I figured it out listening to it this morning. Turns out, it’s math. The percussion part runs through permutations of three low tones and one high tone, with varying repetitions. So the first section goes:

  • L L L H (4x)
  • L L H L (4x)
  • L H L L (4x)
  • H L L L (4x)

And then it repeats, but now each permutation is only repeated three times. Then two. Then one repetition of each permutation, at high urgency and with a fierce percussive attack.

Then: the voices arrive.

And we realize that we have been counting the repetitions and that our breath has been quickening in anticipation of what happens when the pattern ends.

The work is literally minimalistic, but it’s also highly meditative. I don’t think anyone online has specifically written about how Pärt creates this effect, so I figured I’d share.