Wadada Leo Smith (Scott Groller)

If “Ten Freedom Summers” isn’t Wadada Leo Smith’s greatest work, it is, without a doubt, his most monumental. It is a piece of music rich in emotional depth, nuance and historical scope. It is also intimidating in its size.

Smith — a jazz trumpeter, improviser and composer — has been writing and refining his all-encompassing meditation on the civil rights movement, which was a Pulitzer Prize finalist this year, since 1977. It has swelled to more than five hours of music (although it’s still evolving), requiring 10 musicians spread over two ensembles. On Friday, the trumpeter, 71, and his two groups — the Golden Quartet, a jazz band, and Pacifica Red Coral, a string quartet augmented with a harpist and percussionist — began a concert series that would, over the course of three programs and two days at the Atlas Performing Arts Center, cover the bulk of the composition. It’s fairly dense and heady listening.

“Ten Freedom Summers” is organized not as a single piece but as a collection of independent suites, each dedicated to a historical figure or event. Smith’s background is largely in avant-garde jazz, but the material performed on Friday was mostly scored, with only intermittent passages of free improvisation. The music was highly emotive, often somber and elegiac, but also very abstract. As a composer, Smith often eschews recurring motifs, linear progressions or conventional harmonies. There were stops and starts, with momentum often building only to be suddenly diffused as musicians shot off in a different direction.

The material has been developed over an extended period of time, and it seemed as if there were audible differences in style and substance from one composition to the next. “Malik Al-Shabazz and the People of the Shahada,” which was performed by Smith with the Golden Quartet, evoked some of the moody tonalities of fusion-era Miles Davis. “Black Church,” performed by Pacifica Red Coral, was more ponderous, relying heavily on shrill bowed harmonics and droning notes. And even during the same composition, the two sides of the stage could sound very different. Soft piano chords might be answered with shrill alien string tones, only to give way to vibrant, rambling free jazz.

Introspective melodies played in one hemisphere would intermingle with rising dread on the other. The overlap created a strange, compelling dialogue where separate moods could temporarily co-exist, in the way that car stereos in separate vehicles sometimes, unexpectedly, complement one another.

Throughout, Smith’s trumpet often functioned as an anchor element, playing long tones that provided a central narrative to sometimes disparate elements.

In a discussion following the performance, Smith talked about the compositional elements he had perceived while revisiting the Rev. Martin Luther King Jr.’s speeches. “What I found was a beautiful pattern — he would give information, make it have rhyme and have rhythm, and then he took it down a little bit and added new information.” By the end of a few of these cycles, Smith explained, he felt that King would work himself into a spiritual state. It was an interesting note on King. It was also a revealing comment on the inspirations and organizational principles for “Ten Freedom Summers” and the way that history could be woven into such diffuse and otherworldly tones.

Leitko is a freelance writer.