SEAN DALEY, a.k.a. Slug, the rapping force behind Minneapolis hip-hop duo Atmosphere, is in Boise, about to walk into a meet-and-greet session at an indie record store when I reach him on his cell phone. He's already done a block of interviews and he's got a show in town the following day, plus eight other events and performances lined up before he plugs in his mic at the Catalyst in Santa Cruz on Sept. 29.

With a new record out, and perhaps a bit of more to prove now that he's inching up on the four-decade mark, the fair-skinned Minnesotan rhymesayer says he likes the frenzied pace.

"I barely have time to sit down anymore," he says. "I like it that way, though. I think every time you take a baby step toward your goal, you should pick it up and move it a baby step further away, so you can continuously evolve and chase your goal. I mean, what would I do if I achieved all my goals? Maybe take up fishing?"

Atmosphere's new album, a set of two EPs released on Slug's 38th birthday earlier this month, is called To All My Friends, Blood Makes the Blade Holy: The Atmosphere EPs. It's the duo's 13th release and sees Slug at his most lyrically creative.

Instead of delving deep into his usual subject matter—himself—Slug follows the blueprint of his last album When Life Gives You Lemons, You Paint That Shit Gold and lays down epic and (mostly) fictitious narratives through character proxies. Gone are the unabashedly introspective emo raps that fans got on God Loves Ugly and Seven's Travels. This is a gritty mix of poetic short stories about blue collar life, love and loss in the city.

Producer/DJ Ant has slapped a fresh coat of production paint on his typically lo-fi beats as well, with tracks like the funky, circuslike "Americareful" and the distorted, guitar-heavy "Commodities."

The transition away from the narcissistic and brooding image that Slug fostered in his early days and toward a more playful and lighthearted persona has been difficult, he says, but it's been a matter of keeping himself healthy.

"It's easy to paint with dark colors," he says. "I went through a phase of my life when I was drunk a lot and the dark image and myself started to blend together. Once I started to snap out of that I made a conscious attempt to stay away from it, because it's connected to a lot of bad shit. I'm just not into cynicism anymore. I've moved on."

Slug's rosy new outlook on life isn't so new, he contends, saying: "I've felt that way since like '05." But fans who haven't checked in on Atmosphere since the Lucy Ford days can expect all the energy and famous wordplay with a little less of the lyrical self-destruction.

"The name of the game in hip-hop is still descriptiveness," says Slug. "And I've definitely never had a problem with that."

ATMOSPHERE spits at the Catalyst on Wednesday, Sept. 29, at 8:30pm. Tickets are $26 advance/$29 door, available at www.catalystclub.com or by calling 831.423.1338.

Send letters to the editor here.