A little bit of addition has radically reconfigured The Bad Plus.

Emerging from the New York jazz scene at the turn of the century with a repertoire encompassing original compositions and elaborately arranged rock and pop anthems, the collective trio became one of jazz’s most popular and long-running bands.

Founded by drummer Dave King and bassist Reid Anderson, who grew up together in Minneapolis, and Wisconsin-reared pianist Ethan Iverson, the group underwent a major change at the end of 2017 when Orrin Evans, a highly respected player from Philadelphia, took over the piano chair. Discernably altered but still essentially The Bad Plus, the trio seamlessly added Evans’s compositions into the mix on the albums “Never Stop II” (2018) and “Activate Infinity” (2019).

But with the pandemic hiatus and Evans focusing more intently on his own ambitious projects — the romping Orrin Evans Captain Black Big Band has earned two Grammy Award nominations — the pianist decided to move on, leaving King and Anderson at a crossroads. Instead of maintaining the trio format, they ended up recruiting tenor saxophonist Chris Speed and guitarist Ben Monder, brilliant, prolific and well-traveled players who should be far better known. The Bad Plus introduces the new lineup to the world at Yoshi’s this weekend, Sept. 25-26.

“One thing we wanted to do was get away from piano,” Anderson said. “It made sense to have guitar and saxophone, which is classic instrumentation. But more importantly, both of those guys are really interesting musicians with very personal approaches. They’re also people we have longstanding relationships with. It all made sense.”

While still strongly associated with dramatic interpretations of songs such as Black Sabbath’s “Iron Man,” Blondie’s “Heart of Glass,” and Tears for Fears “Everybody Wants to Rule the World,” The Bad Plus primarily serves as a vehicle for Reid and King’s writing. After the Yoshi’s run, the band heads back east to record an album of new material they’ve written for the quartet configuration. Rock and pop covers don’t figure much into band’s book anymore.

“That’s always been the secondary point of the band, a small part of the exploration that helped us find our sound together,” Reid said. “It’s really evolved into Dave and I being the compositional and conceptual force behind The Bad Plus. It’s a delivery device for our songs. At the same time, we all embrace pop and rock music in general.”

There are so many overlapping associations between the four musicians that the most notable development might be that The Bad Plus is bringing Monder and Speed together in the recording studio for the first time, though they’ve played together informally and toured in various settings over the past three decades. In fact, Monder was the first musician Speed reached out to when he moved to New York in 1992, which led to a gig at the Knitting Factory.

“Ben is one of those New York secrets,” Speed said. “He’s the heaviest guitarist I know, and it’s such a dream to get to play with him.”

Like Speed, Monder is best known as a collaborator who brings a jolt of creative energy into any musical situation. He’s released 10 albums as a leader or co-leader, while appearing on more than 80 as a sideman, including projects with composer Maria Schneider, tenor saxophonist Donny McCaslin, drum legend Paul Motian, and David Bowie’s “Blackstar.”

Speed has been far more present in the Bay Area over the years, while rarely performing under his own name. Some of his recent gigs include Yoshi’s with Dave King Trucking Company and the SFJazz Center with Broken Shadows, a quartet with King, Reid, and alto saxophonist Tim Berne that focuses on compositions by Fort Worth saxophone comrades Ornette Coleman and Dewey Redman.

Living in Los Angeles since 2017, Speed thrives on digging deeply into the idiosyncratic details of a band’s music (a longtime Brooklyn resident before his move to LA, he documented the work of many neighboring players on his stylish label Skirl). Getting into the nitty gritty of The Bad Plus book is like catnip to him, particularly because he’s seen the group perform dozens of times.

“I’m feeling like an archeologist, scraping away and seeing what’s underneath,” he said. “I always wanted to have a band where that’s all we did. The reality has been doing a gig here and a gig there, bouncing around a lot because most bands can’t work steadily. I’ve always respected The Bad Plus for saying, we’re going to focus on this. It’s a situation everybody is committed to 1,000 percent. That’s how the music really gets deep.”

Contact Andrew Gilbert at jazzscribe@aol.com.

THE BAD PLUS

When & where: 7:30 and 9:30 p.m. Sept. 25, 7 and 9 p.m. Sept. 26 at Yoshi’s, 510 Embarcadero West, Oakland

Tickets: $29-$74; 510-238-9200, www.yoshis.com