In the winter of 1992, New York composer Phil Kline wrote a multi-track piece of electronic music that was exactly 45 minutes long—the length of one side of a cassette tape. He invited some friends to a meeting point in Greenwich Village and handed out boom boxes with the tapes inside—different tracks for different machines. On his count, they all pressed play at the same time and walked around, creating what people say was an eerily beautiful cloud of "sound sculpture" wandering through the street.

"In effect," Kline later recalled, "we became a city-block-long stereo system."

The piece was called Unsilent Night, and it's become a holiday tradition in dozens of cities in Europe and North America, an exercise in counter-caroling that will be performed this year from Brussels to Tucson. (The New York event, organizers, have said on their website, may include elements of the recent Ferguson demonstrations, but they ask that any protests be "visually based. We will be a peaceful island walking through the city streets.")

This Saturday at 5 p.m., people are invited to meet at On the Boards for Seattle's Unsilent Night. The more folks show up with devices—phones, boom boxes, whatever—to play the music, the more powerful the experience can be.

You can hear a sample of what Kline calls "a little electric massage of Advent-y stuff" here:

But I'm guessing you have to be out in the street, surrounded by all the tracks, to get the full effect. Kline has also called it "ventriloquial music" that seems to come from the ice below, the sky above—everywhere and nowhere at the same time.

Hopefully, somebody will spike the eggnog.