Tobias Liu, Contributing Photographer

For 90 minutes, sustained string sounds, interrupted only by moments of silence and the occasional foot shuffling, reverberated around the circular walls of the Schwarzman Dome. The sounds descended through harmonic landscapes and shimmering microtonal frequencies, at times serene and hazy, at times throbbing and suffocating.

On Friday night, the JACK Quartet performed Catherine Lamb’s “divisio spiralis” at Yale.

Hailed by The New York Times as “our leading new-music foursome,” the Grammy-nominated JACK Quartet has become a genre-defining leader in contemporary classical music. They are composed of violinists Christopher Otto and Austin Wulliman, violist John Pickford Richards and cellist Jay Campbell, the only musician to win two Avery Fisher grants. The group currently serves as the Quartet in Residence at the New School in New York City.

“Given our keen interest in unconventional performance practice and the distinctive architecture of the Dome, it seems only fitting that the JACK Quartet will enliven the space with a work that plays so beautifully with its spatial qualities and acoustics,” said Rachel Fine, the Schwarzman Center’s executive director.

The JACK Quartet champions new string quartet music through commissions and close collaborations with composers. Their JACK Studio initiative, which selects composers for reading sessions and residencies with the quartet, offers composers paid opportunities to develop new work in an attempt to “dismantle outmoded classical music pipelines for composers,” according to their website.

“divisio spiralis,” written for JACK in 2019 by Lamb, is a roughly 90-minute piece that explores and pushes the boundaries of harmony with the sustained sound of strings. 

Lamb’s genesis of the piece derives from Erv Wilson’s 1965 organization of the overtone series as a logarithmic spiral. According to the program, she sought to “describe harmonic space as numbers in repetition and interaction … blooming outwards with each new prime and composite.”

The work uses microtonal tunings based on the overtone series of a 10-hertz fundamental. Every note is an overtone of this 10-hertz frequency, a frequency slow enough “that it’s basically a rhythm,” and the music shifts “freely” through these different pitch collections, according to Campbell. 

For Campbell, the contradiction between balancing the “numerical perfection” with the “materiality and imperfection of the physical world” is what makes the piece so beautiful. 

While the goal of the piece is to play exactly the frequency each player is supposed to play with each other, the concept of perfection intonation is mathematically impossible: if frequency is a function of time, it takes an “infinite amount” of time to say something is in tune.

“[This contradiction] changes how we relate to each other as musicians — changes, for me, how I relate to the passing of time,” Campbell said. “[‘divisio spiralis’] was a life-changing piece.”

Striving for perfection in intonation for a work that relies solely on patterns of resonance and harmony to make its impact pushed the group in an “extreme direction.” Campbell described pre-rehearsal preparation with sawtooth wave mockups of the piece and a month during the pandemic where they “spent all their time on just [‘divisio spiralis’].” The quartet also experiments with playing with tuners, which allows them to isolate their individual pitch and read their frequencies as they play. 

Playing long, slow notes can be surprisingly physically taxing, said Campbell. Mentally, Campbell tries to balance feeling comfortable enough to be physically flexible with a “hyper-focus” on the intonation while ensuring he is “in the present” and is being “swept away” by the piece.

At the start of the performance, Wulliman encouraged the audience to make themselves comfortable. “It’s a long journey,” he said. Throughout the 90 minutes, some audience members walked or found a different seat, some stood and stretched before sitting back down and some stood and remained standing.

Jennifer Harrison Newsman, Schwarzman Center’s associate artistic director, said she found the group’s flexibility a unique departure from a traditional classical performance.

“It’s so special that we can offer a durational piece that allows you to come in and respond with your own, sitting at such a proximate location to artists at that caliber,” she said.

Registration for the concert was free. On Dec. 15, the Schwarzman Center will present the AMOC* production of John Adams’ “El Niño: Nativity Reconsidered” with Julia Bullock. 

Correction, Feb. 12: This article has been adjusted to spell “divisio spiralis” with correct casing.