At least when it comes to writing, Karl Denson seems to have swapped his saxophone for a guitar.

Denson started playing guitar about three or four years ago, using it to write at least one song, “My Baby,” on his 2014 album with his band Tiny Universe, “New Ammo.” Since the album’s release, Karl Denson’s Tiny Universe has toured with two guitarists — the band now features longtime six-stringer D.J. Williams and newcomer Seth Freeman on slide and lap steel.

While Denson doesn’t play guitar live, he continued to use it as a writing tool on the band’s upcoming album, tentatively titled “Smart Boy” and due out sometime in the spring.

“You know, I think it simplified the (songwriting) process,” Denson said from Miami, only hours before leaving on the 15th annual, five-day Jam Cruise, “because I’m so illiterate on the guitar that whatever I do is perfectly simple.”

Perhaps more surprisingly, Denson passed the horn arrangements for the new record off to Mark “Speedy” Gonzales of Austin, Texas, Latin funk group Brownout. Denson does play on the record — his muscular saxophone and flute are key elements on any Tiny Universe record (or anything Denson is involved with, period) — but he said he was more than happy to let Gonzales take over arranging duties.

“Sometimes, you know, you don’t need to do everything; there’s not time in the day to do everything,” Denson said. “And he’s a better horn writer than I am, to be perfectly honest. His horn arrangements are amazing, and he does them so fast. It’s pretty amazing to watch. I’ll still write some horn arrangements, but definitely they pale in comparison.”

When it comes to his time, at least, Denson isn’t kidding. His recent performance schedule says it all: After celebrating Denson’s 60th birthday Dec. 27 with a blowout performance at The Fillmore in San Francisco, Tiny Universe kicked off its Runnin’ With the Diesel tour with Jam Cruise. The tour stretches through March, including a stop at Volcanic Theatre Pub on Tuesday.

Before he returns to Bend, Denson will once again share the stage with The Grateful Dead’s Phil Lesh at Terrapin Crossroads in San Rafael, California, on Friday. Denson debuted at Terrapin Crossroads last summer, joining Phil Lesh & Friends for the band’s set. Then in September, Lesh joined Tiny Universe for its own set at Terrapin Crossroads.

“It’s very, I would say, liberating,” Denson said. “The whole Dead thing, it makes sense. You know, not having grown up a Deadhead or anything, I don’t know that material as well as a lot of people do, but he’s very trusting in my musicianship and my band’s musicianship. This time around I think we’re gonna actually play some of our own stuff. He wants to mix it up with us, so it’s gonna be even more fun I think.”

Then there’s The Rolling Stones, with whom Denson has toured since late 2014 replacing late saxophonist Bobby Keys. He called the experience “surreal.”

“Don’t f— up, pick the right stuff, you know” Denson said, describing his mindset his first time onstage with the Stones. “It’s just one of those gigs where you play some sick stuff, and people will treat — it would usually be very daunting. But with those guys, it’s really just, you’re playing with those four guys. That’s more of what you’re thinking about; it’s not really the audience very much.”

He landed that gig through a phone call from an old friend, Lenny Kravitz. Denson got his start in the music business in Kravitz’s band, appearing on the guitarist’s 1988 album “Let Love Rule” as well as subsequent records “Mama Said” and “Are You Gonna Go My Way.” He toured with Kravitz through 1993, and by the time he quit he had released his first solo album, the straight-ahead jazz outing “Blackened Red Snapper.” Denson would subsequently go on to found jazz group The Greyboy Allstars (which still records and tours, with dates lined up this year) and eventually Tiny Universe.

Tiny Universe has been Denson’s main focus since the band’s return after a five-year hiatus in 2009 with the album “Brother’s Keeper.” The new version of the band kept busy with a number of tribute tours, including shows dedicated to The Beastie Boys (with Slightly Stoopid), The Rolling Stones’ “Sticky Fingers” album (with Anders Osborne) and Ray Charles (with Zach Deputy), in the next five-year wait between “Brother’s Keeper” and “New Ammo.”

The band continues to evolve on the upcoming “Smart Boy.” Whereas “New Ammo” featured a four-man horn section, some hard-rocking instrumentals and covers of The White Stripes (a flute-driven “Seven Nation Army”) and The Beastie Boys (“Sure Shot”), “Smart Boy” will focus on songwriting and singing, Denson said.

“You feel like you’re trying to complete the sound of the band,” Denson said. “I think that at the time, ‘New Ammo’ was where we were going in terms of kind of soundtrack-y, big horn arrangements, kind of stuff. This record has really been more about trying to write good songs, vocal songs, writing lyrics and that whole process. It’s — they kind of go back and forth like that in terms of, one record’s about playing, one record’s about writing and singing, and that’s kind of how I’ve done it over my career.”

On “New Ammo,” the whole band got in on the writing process, and that collaborative spirit carried over to the writing sessions for the new songs. The band’s current lineup features Williams, Freeman, returning drummer Alan Evans (of Soulive), Greyboy Allstars’ bassist Chris Stillwell, keyboardist David Veith and trumpeter Chris Littlefield.

“Earlier in my career it was mainly me writing tunes and then bringing it to the band,” Denson said. “… These days I trust the band enough where it’s become a collaborative effort. So a lot of times, especially with this guitar writing kind of stuff, I have to trust my guitar players a bit more to flesh things out for me.”

“Earlier in my career it was mainly me writing tunes and then bringing it to the band. … These days I trust the band enough where it’s become a collaborative effort. So a lot of times, especially with this guitar writing kind of stuff, I have to trust my guitar players a bit more to flesh things out for me.”— Saxophonist and bandleader Karl Denson

What: Karl Denson’s Tiny Universe

When: 9 p.m. Tuesday

Where: Volcanic Theatre Pub, 70 SW Century Drive, Bend

Cost: $25 plus fees in advance, $30 at the door

Contact: volcanictheatrepub.com or 541-323-1881