"When Sō Percussion started working with Caroline, we noticed that her first creative step, before writing any music, was to suggest sounds. Then, she would step back and listen," Sō's Adam Sliwinski (pictured second from right) writes in his liner note to the new Caroline Shaw and Sō Percussion album, Rectangles and Circumstance, out this Friday on Nonesuch. You can read his note here:

I once asked Caroline Shaw how she knew she wanted to be a composer. She said, “When I perform pieces by other composers, I often hear the music going somewhere else in my head.” For her, the urge to compose manifests not only as creating from scratch, but as listening and responding, and the question of what comes next is just as important as where to start.

When Sō Percussion started working with Caroline, we noticed that her first creative step, before writing any music, was to suggest sounds. Then, she would step back and listen. The first piece she composed for us was the meditative Taxidermy, written for mallet instruments and flowerpots. On the day we started working on it, she brought in a few ideas of sounds to hear us play (striking softly and steadily in unison, rolling, tapping with fingers). As a result of this careful listening, the flowerpot gestures in the eventual piece felt perfectly timed and distributed, calmly confident in their simplicity.

After collaborating in a similar way on 2017’s Grammy-winning composition, Narrow Sea, we started to co-compose music for Let the Soil Play Its Simple Part, which was released on Nonesuch Records in 2021. Caroline’s gift for deciding what to do next animated the process, no matter whose ideas we were trying. After a few years of touring Let the Soil Play Its Simple Part together, with a pandemic in between, we came to record our second album, Rectangles and Circumstance, as a road-tested band who knew each other’s strengths, weaknesses, and tendencies intimately.

Most of the songs started with instrumental pieces or fragments of pieces from Sō’s Jason Treuting or Eric Cha-Beach. Sometimes those sketches came fleshed out with verse and chorus structure; other times they started as exercises or variations for us to jam on.

Eric first introduced “Sing On” as one of his characteristic explorations of number-dividing at macro and micro levels. The song is organized around phrases of four bars with seven pulses each (7/4 meter), each of which is divided into two sets of seven smaller pulses (7/8 + 7/8). The opening pulses therefore divide each bar neatly in half, giving no indication of their “odd” character until a tiny hitch in each fourth bar, which is divided as four big pulses plus three (8 + 6 small pulses). Is knowing this necessary to enjoy the song? No, because Caroline composed a gently rollicking four-bar chord progression with her Helicon voice synthesizer, which creates a harmonic structure for a joyful and climactic song. In fact, I don’t remember us ever discussing the metrical scheme with her.

The same process applies when we are making one of Caroline’s songs. This entire collaboration started with us taking extra time at the end of the Narrow Sea sessions to make our version of her piece “Other Song.” We recorded a base layer of the tune and its elements, then stacked up multiple passes of percussion sounds, adding and subtracting them with the expert help of our co-producer and engineer, the estimable Jon Low. On this album, we made a new arrangement of Caroline’s song “And So.” As with “Other Song,” Jason and I outlined the structure with drums and piano. Once that was complete, all of Sō added flowerpots, Fender Rhodes, vibraphone, organ, steel drums, more percussion, and vocals.

The first stage of this layer-making occurred at Guilford Sound, a state-of-the-art recording studio in a bucolic hilltop setting in Southern Vermont. Each time we record there, it feels like a retreat: just the kind of environment for the intimate collaboration which makes these songs flourish. Most days at Guilford, Caroline could be found either tucked into the capacious armchair in the control room, with a keyboard and headphones on, or in a vocal isolation booth. Sometimes we could hear her trying out melodies and harmonies over our tracks, while other times she would be working things out privately, so that only she and Jon could hear. With Caroline, this process of listening and experimenting goes on longer than with any other composer I’ve ever worked with. She waits for sounds to ripen, which may be one reason why organic symbolism is prevalent in much of her music.

After the Vermont sessions, we had nearly completed the instrumental tracks. Caroline returned to them that fall in New York, in smaller sessions with Eric Cha-Beach (who was the lead producer from Sō Percussion on the album) and Jon Low. It was in the New York sessions that she started to fit poetry to new melodies, grabbing bits of the recordings we’d made. Sometimes she composed a melody to sing over the completed track; other times, such as with “Rectangles and Circumstance,” she pulled the track apart and reassembled it with new material.

“The Parting Glass” started as a composition by Jason Treuting. He was fascinated by J. S. Bach’s Jesu, Joy of Man’s Desiring, which is in 9/8 meter (nine small pulses to a bar, with a big “walking” pulse every three small pulses, three to a bar). He conceived of a piece for all of Sō Percussion around a vibraphone playing in 9/8, in which he took the original chord progression from Bach’s piece and ran it backwards, altering it in places as the harmonic structure took shape. It is unusual for Jason to write Bachian chord progressions like these, and it was a fresh spin on his style.

When we performed the composition for Caroline, the harmonies and repetition reminded her of an Irish reel or some other sort of perpetual-motion music, and she suggested a brief switch to a related minor key during the transitional sections, a matter of changing one note in the mode. Later, after the Vermont sessions, Caroline found the traditional Scottish song “The Parting Glass,” adapted the lyrics, and composed a new melody to fit within Jason’s harmonic cycles.

Many of Jason’s songs contain noisy elements that mesh with the drums, for which he uses a Roland SPD-SX drum pad to trigger sampled sounds. He sampled excerpts from his own previous compositions, and made new samples of sounds such as piano chords (sometimes with birds chirping in the background), while stretching, inverting, or reversing them along the way. Most of them are altered enough to be unclear, and they scatter a gritty patina on top of Jon Low’s pristine acoustic sounds. This is especially true for songs such as “Like a Drum” and “Slow Motion.”

As both a songwriter and a classical composer, Caroline is accustomed to writing lyrics as well as setting them. In Let the Soil Play Its Simple Part, she and I pulled excerpts from James Joyce’s Ulysses, which I was reading during the time of that recording session. Several songs on that album used fragments from Ulysses in their lyrics. Going over texts with her is like working on music: I collect a handful of poems and send them over to her, waiting to see if anything catches her interest, then I modify my search based on her feedback.

For this album, Caroline, Eric, and I sourced a group of 19th-century poems that shaped its expressive mode. Most of them are by women. In Let the Soil Play Its Simple Part, two of the most affecting songs are “To the Sky,” which is a text from the Sacred Harp by the 18th-century poet and hymnist Anne Steele, and “A Gradual Dazzle” by the contemporary poet Anne Carson. During the making of Rectangles and Circumstance, I was reading a newly revised Penguin Book of English Verse, which includes far more female poets in its anthology than the volumes I grew up with. We ended up using verses by Christina Rosetti, Emily Brontë, Emily Dickinson, Gertrude Stein, and William Blake. In some songs, particularly “Sing On,” Caroline freely mixes the poet’s words with her own.

The title track, “Rectangles and Circumstance,” proposes a reflection on technology-saturated modernity. In many ways, the 19th-century texts remind us that love, loss, and true connection will always be our human obsessions, no matter what comes along to mediate them. As is usual with our creative process, these connections emerged rather than being planned. For instance, “Rectangles and Circumstance” was one of the last tracks to come together.

The lyrics on this album by members of the band contain wordplay that explores the same profound feelings explored by Blake and Dickinson. Eric’s “Who Turns Out the Light” expresses the loving but exhausted thought patterns of a parent trying to coax and calm a young child (and themselves). Caroline’s lyrics on songs like “And So,” “Slow Motion,” and “Rectangles and Circumstance”—the latter two of which she wrote with her Ringdown bandmate, Danni Lee—often employ a meta-layer of words that talk about structures of words:

And so, you say, the saying goes
A rose is a rose is a rose is a rose
Is a rose is a rose is a tired rhyme
But in the verse there’s always time

These playfully recursive lyrics sometimes hint at loss and futility:

Or will we fade to stanzas of the dust
That, I suppose is all we were and all we’ll be?

The meta-layers suggest that the game of words is sometimes all that’s available to us to communicate what Wordsworth called “thoughts that do often lie too deep for tears.”

We produced such a large body of material to record in Vermont that it was busier and more task-oriented than our sessions for Let the Soil Play Its Simple Part. On the last day of recording, Josh Quillen introduced an idea that recalled our version of ABBA’s “Lay All Your Love On Me,” which Caroline and I had arranged for the previous album. He was inspired in part by an experiment he had conducted with Thelonious Monk’s “Round Midnight” on steel pans, where he recorded the song at almost half tempo to hear all its fascinating details.

All five of us attended The Yale School of Music for graduate school, where each year at convocation, there was a tradition of the students and faculty singing Franz Schubert’s song “An Die Musik” at the beginning of the ceremony like a congregation in church. The song is a secular hymn of gratitude to the art form of music, with words by the early 19th-century German poet Franz von Schober. It is gorgeous, and famous for its complex bass line.

Josh and Caroline concocted their own warped version of the song: They printed out the music, set a very slow tempo, and guided the rest of us to perform multiple recording passes, in which each performer was free to pick out notes from the harmony and bass line, but in which we mostly avoided the main melody. The result is a glacial, minimalist version that is almost three times longer than the original. Without the melody, and at this pace, Schubert’s magnificent voice-leading, his small passing notes in the bass voice, and his luscious harmonies all seem to be suspended in the air. This leaves the ghost of a structure, like a ruined building or an ancient underwater city.

I can’t imagine making this music without these six people, including Jon Low. Jon started shaping our sound when we first recorded “Other Song.” In many ways, our enthusiasm for working this way together was a result of how quickly and effortlessly Jon pulled that track together that day, helping us to believe that this was a worthwhile effort. Rectangles and Circumstance is a manifestation of his precise ear and brilliance for engineering, Caroline’s flexibility, compositional vision, and beautiful voice, and the unique interests that each of us in Sō bring to our instruments and musical ideas. It was made with love, and we are honored to share it with you.

—Adam Sliwinski