Hays, left, and Ryan Holladay have turned the “primal scream” of anti-Trump Americans into recurring performances by a string quartet at the base of the Capitol. (Ben Chetta)

It’s a protest so peaceful, passing joggers, tourists and selfie-posers hardly notice it’s taking place. On the last Sunday of each month in 2017, an anonymous string quartet assembles outside the U.S. Capitol to perform an interpolation of “Hail, Columbia,” a song originally composed for George Washington’s inauguration in 1789 — and each time they gather to play, notes are expunged from the score.

The music itself is understated, but the metaphor isn’t: As the first year of Donald Trump’s presidency unfurls, the patriotic song disintegrates into silence. The piece is called “Columbia Diminuendo,” and it’s the work of Hays and Ryan Holladay, two Virginia-raised brothers who previously composed a handful of site-specific works for the Mall under the name Bluebrain.

In 2010, the Holladays organized an enchanting “Cherry Blossom Boombox Walk,” an interactive performance that ended near the Tidal Basin in a shower of pink petals. And in 2011, they released “The Mall,” an astonishing, still-ahead-of-its-time iPhone app that uses GPS technology to trigger different pieces of music based on the listener’s physical location. Now, with the help of Washington’s Transformer gallery, the brothers — who have since relocated to California — are staging a more sobering experience that utilizes the Mall as a space for public protest and private contemplation.

“One of the ideas behind this was to create an opportunity for people convene and share a different emotion than outrage,” Ryan Holladay says of the project. “The primal scream that we’re seeing is vital and important, but we wanted to create a platform for people to express something different — people coming together around something that’s reflective.”

“Columbia Diminuendo” will be performed Sunday at noon — and again at noon on the last Sunday of every month for the duration of 2017 — near the Ulysses S. Grant Memorial, First Street NW. Updates on Twitter: @transformerdc. hrholladay.com. Free.