A so-called “big band” in jazz has a particular definition. Usually it means 17 or more musicians: four trumpets, three or four trombones, four or five saxophones, plus a rhythm section of piano, bass, drums, and maybe a guitar. By the 1930s, “big band” music had evolved into a distinct and extremely popular style. Duke Ellington, Benny Goodman, Count Basie, Glenn Miller, and others defined an era in American popular music, playing in ballrooms for dancers and being broadcast by radio into homes across the world.
However, the popularity of that sound and the economics of keeping big bands going faded quickly with the advent of rock and roll and the electric guitar. Starting as early as the mid-1940s, jazz musicians themselves began to tire of the restrictions that big band arrangements placed on the length and liberties they wanted in their improvised solos, begetting a more adventurous era in jazz, “bebop”.
However, a great art form never dies, even if it grows less popular. Modern big bands emerged as early as the 1940s. They deployed bebop, cool jazz, and Latin Jazz elements, and even the avant-garde pianist Cecil Taylor worked in the format for years, using it like an abstract expressionist painter. In the new century, big bands led by Maria Schneider, Darcy James Argue, and John Hollenbeck have revolutionized the format again, showing how flexible and expressive it remains to have all those colors at your disposal.
Unseparate is the second recording from a big band led by Anna Webber and Angela Morris, both composers and woodwind players on the creative music scene. Their first outing, Both Are True, was released in 2020, and it was a pure joy—smart, complex new-century jazz but also music that flipped through sections of old-school swing, punchy brass arrangements, and grooving guitar solos.
The new recording is equally rich and possibly more ambitious. Most plainly, it includes a set of Webber compositions that follow up on her superb work on the solo album Shimmer Wince—writing that uses concepts of “just intonation” to create unique settings and challenges for jazz improvisers and ensemble players.
However, that one idea doesn’t define this new set. The larger idea is simple: Webber and Morris want to explore the vast array of musical ideas an 18-piece big band offers, with as much individual freedom as possible. Though they are separate composers, a joint vision and single band bring all the tracks together. The music tends to push outward beyond tradition and then fuse back into consonance. Lots of strategies for exploration are presented, but the LP sounds organically whole.
Webber’s four “Just Intonation Etudes for Big Band” open the record in bracing style. “Just intonation” is a system of scale intervals (the pitch distances between C and another note, say) based on whole number ratios, which varies from how pianos and other “fixed interval” instruments are tuned. That may sound like a technicality, but here’s what it means to a listener. These pieces feature the group’s horns playing harmonies that waver and phase by microtones, slipping in and out of slight dissonance by compositional design, or at least what our ears are trained to hear as dissonance.
The etudes begin with the Webber/Morris Big Band playing a set of long-held, majestic harmonies that sound sterling and then, in an instant, sour. It seems like a thesis statement of a sort, as this will happen during the rest of the suite as well, to interesting effect. The second etude, “Pulse”, has two thrilling parts, united by the motif of stabbing horns or horns-plus-vibraphone in contrapuntal conversation with soloists and a shifting, syncopated throb by the rhythm section.
The sense of the harmonized horns being mildly dissonant emerges in the second section, as the Webber/Morris Big Band again hold some long tones. As Yuhan Su solos on the vibes (not a just intonation instrument), the sweet-sour quality of this experiment seems at its best: the arrangement is precise and rhythmically heart-pounding, but the shimmer of slight dissonance gives it an extra layer of electrical buzz.
Part three, “Tibre”, is built on a slow repetition of one chord played by woodwinds, as a soloist and the brass wiggle abstractly around the tonal discomfort, which then builds into a rollicking big-band rumble. The piece suggests to me that all large-band music is built, to some extent, on how instruments rub against each other with bits of harmonic imperfection—that this is a real part of what makes it sonically exciting.
Venturing beyond the just intonation suite, the whole album makes even more sense. Morris is a composer with a vast range who is also using the 18-piece band to showcase the format’s strengths and timeless appeal. In “Unseparate 2”, she unleashes several players in a kind of New Jazz Dixieland, improvising collectively until they converge on an ambiguous tonal center.
In the next track, “Microchimera”, she gives the Webber/Morris Big Band a sexy backbeat groove and sly harmonies, which still find their way into modernist bursts of dissonance, each in turn transformed into a passage of great beauty or funky appeal. My favorite moment here is when pointillistic and harmonic flute/piano segues back into the groove, with the ensemble covering the flute improvisation in sumptuous harmony.
Morris’ “Habitual” is another outstanding construction and performance. The score sets all 18 pieces of the ensemble in rotation around each other, first in staccato pops and eventually in flowing lines with powerful bass notes rising in a propulsive but odd time signature. As the group cut out, we get a potent solo piano performance from Marta Sanchez, punching the lower end of the keyboard, swirling in the upper register, then inviting in Adam Hopkins’ bass and Jeff Davis’ drums. We get to see how the same idea works at the level of a piano trio, and then as an Ellingtonian half-time arrangement featuring Lisa Parrott’s baritone saxophone.
Each of the other longer performances here is a notable modern work for big band. “Missed/Mist” by Morris plays with the sonority of horns as they push and pull against each other, notated or improvised. The fourth Webber etude, “Metaphor”, features a memorable melodic idea that unspools over ten minutes in a stately, suspenseful manner, with a brilliant trombone solo from Tim Vaughn that eventually roils into a flowering of free improvisation. Webber’s “Spur 7: Metamorphosis” takes a thumping waltz time and pushes it into a polyrhythm that owes a bit to Chico O’Farrill and a bit to Steve Reich, resulting in an extended, exultant solo by Jay Rattman on alto saxophone.
Whether the area of exploration involves “just intonation” or not, the Webber/Morris Big Band sound like a large ensemble out along the territory with one eye back on the tradition. This isn’t avant-garde music — or, at least, in 2025 that description no longer fits. Anna Webber and Angela Morris are simply committed to letting a large band take the kinds of compositional, structural, and improvisational liberties that small bands routinely take in the new century. However, just as importantly, they use the additional layers of sound that an 18-piece band offers to make their explorations particular to this format.
Webber/Morris Big Band’s Unseparate, true to its name, puts its colors and rhythms up against each other to buzz, shimmer, and pulse in ways that no band can—or has yet tried to—match.