It’s a big, straight-out-of-New Orleans double bill: Galactic plus Troy “Trombone Shorty” Andrews and his band, Orleans Avenue. Two of the Big Easy’s funkiest acts, and they’re playing Tuesday at the Varsity Theatre.

Galactic and Andrews are doing a four-show mini-tour this month, covering Baton Rouge, Mobile, Alabama, Houston and Dallas.

“We’ve known Shorty since he was the little kid with the big trombone,” Galactic keyboard player Rich Vogel said last week. “We watched him coming up. Like so many other people in this town, we recognized his talent a long time ago.”

Andrews and Galactic previously toured together in the Northwest in 2013.

“It’s a natural pairing of two bands,” Vogel said. “We’re different but related enough to make a cohesive show. So when Troy became available to do a few shows in December, we jumped at it.”

2015 is Galactic’s 20th anniversary year. But the band did nothing to mark its two decades of existence.

“It slipped by us,” Vogel said without regret. “We have been consistently at it for those 20 years. We don’t spend a lot of time stopping and reflecting.”

Despite the lack of anniversary observations, Galactic did release a new album in July, “Into the Deep.” A stylistic variety show, the project’s guest stars include Macy Gray, Mavis Staples, JJ Grey and New Orleans singer and member of the Honorable South, Charm Taylor.

Taylor’s “Right On” song proved to be a sleeper track.

“I love ‘Right On’ with Charm,” Vogel said. “It crept up in popularity.”

Gray adds her unmistakable voice to the soulful, piano-based title song “Into the Deep.”

“We had the songs and it sounded like a good one for Macy,” Vogel said. “She took it, finessed it, changed some lyrics and made it that much better.”

Working with gospel and R&B star Staples for “Does It Really Make a Difference” was especially exciting. Staples and Galactic had previously performed at some of the same festivals. She also made a guest appearance with the band on stage.

“That was such an honor, to meet Mavis and have her sing with the band,” Vogel recalled. “So we reached out to her because we thought ‘Does It Really Make a Difference’ lent itself to what she does.”

Galactic band members Ben Ellman and Robert Mercurio flew to Chicago to be in the studio while Staples recorded the song.

“We had our fingers crossed,” Vogel said. “Mavis said, ‘Yes.’ It all worked out. I love that one.”

Collaborations, including the vocal partnerships for the “Into the Deep” album, keep taking Galactic to new frontiers.

“We in the band have a long-term partnership that’s special,” Vogel said. “A certain comfort comes from playing with the same guys for so long. But you have to figure out, ‘What are we going to do with it now?’ It’s energizing to bring in new people and work with them.”

In September in New Orleans East, Galactic also staged The Landing, its first music festival.

“For a first year, I thought it was great,” Vogel said. “I think it will build nicely.”

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