David Longstreth's Dirty Projectors Do "Swing Lo Magellan" Dirty Projectors From left, Olga Bell, David Longstreth, Nat Baldwin, Amber Coffman and Haley Dekle at the Music Hall of Williamsburg. An easygoing beat, a two-chord 1960s soul vamp, a smooth and fairly symmetrical melody: could that be the title song for an album by the usually jumpy, convoluted, math-rock, Afropop, art song band Dirty Projectors? And it was how the band started its set on Monday night at the Music Hall of Williamsburg (webcast live on YouTube). The set focused on songs from the album, "Swing Lo Magellan" (Domino). Mr. Longstreth, the leader, focused on the group's new album. David Longstreth has written some of his most approachable tunes for this new album, with fewer of the sudden leaps, meter shifts, contrapuntal vocals and stylistic jumps than Dirty Projectors are known for. The change apparently leaves him ambivalent about the idea that the band might be growing too pop. Instead of letting pretty melodies cruise suavely along, he undermines them with speed bumps and potholes. In "See What She Seeing," a song about joyful infatuation, the percussion sputtered fitfully instead of providing a beat, while keyboard and guitar effects made chords waver in pitch instead of providing a dependable backdrop. "About to Die," which hinted distantly at doo-wop, had an arrangement full of intricately planned stops and starts, offbeat drum rumbles and hurry-and-pause bass lines. It was the kind of complexity Mr. Longstreth has always built into Dirty Projectors" songs. Tricky, pointillistic older material like "Cannibal Resource" or "Beautiful Mother" had its own fitful momentum, hopscotching melody lines and jump-cuts between pretty three-part female vocal harmonies and barbed guitar chords. But in those songs, all the quirks were working together; the music was odd on every front, and all the more appealing for it. The newer material comes closer to more standard genres, particularly soul and R&B, yet fights hard against them, as if it's battling against itself. Dirty Projectors" newer songs haven't given up their strangeness, particularly in their lyrics. "Maybe That Was It" imagines rot and putrefaction in a ballad with guitar notes that are deliberately bent out of tune. In "Just From Chevron," the band's three women sang sweetly about an oil worker being fatally injured on the job. Then Mr. Longstreth took over with the man's dying words, saying he was happy to be joining the fossil fuel supply: "Wherever the people will drive/That's where I will survive." But the set ended near where it had begun, with "Impregnable Question." The rhythm was back to the 1960s, with emphatic accents on each beat as if the band were putting "Memphis soul" in quotation marks; the women harmonized like soul backup singers as Mr. Longstreth vowed, "You are my love and I want you in my life." It was a love song, and there was no way Dirty Projectors could get around it.