Earlier this year, Bela Fleck and the Marcus Roberts Trio captured something special on the album “Across the Imaginary Divide.” Sunday at the Berklee Performance Center, they set it free.

Banjo player Fleck, pianist Roberts, bassist Rodney Jordan, and drummer Jason Marsalis capped the Berklee BeanTown Jazz Festival with a spirited show that gathered various traditions — bluegrass, ragtime, blues, classical, folk — and booted them forward.

As the name of their collaborative album implies, Fleck and the Roberts trio sought to erase any perceived boundary between their respective musical traditions, bluegrass and jazz. Yet in doing so, nobody turned away from his roots. Instead, each musician responded to the compositions’ fresh ideas from an established base, be it Fleck’s fleet picking or Roberts’s sophisticated playing.

Nothing feels forced in this collaboration, and the live performance beamed with good humor. Fleck and Roberts, who were huddled together onstage, frequently chased each other’s riffs and melody lines before breaking free for a virtuosic solo. Marsalis and Jordan drove tunes when not holding down rhythms, and Jordan and Fleck locked into quirky little conversations throughout the nearly two-hour concert

Continue reading below

Fleck and Roberts are both masters of musical dialects and spoke to each as such. “Kalimba,” for instance, was a rangy piece that opened with Fleck invoking a gypsy jazz inflection that Roberts met with an airy, atmospheric flutter of notes.

Roberts told the audience that ragtime is like water in jazz; it’s in everything. When the quartet did “That Ragtime Feeling,” the water was brought to a boil, creating progressive ragtime.

In keeping with the program’s sense of exploration, Roberts introduced the encore by saying he never imagined his band would be playing bluegrass. Then before launching into Fleck’s frenetic “Cheeseballs in Cowtown,” Roberts assured, “We like it.”