Michael McDonald had been a key collaborator on the Doobie Brothers' platinum-selling Top 10 album Takin' It to the Streets. He wrote or co-wrote four of the 1976 LP's nine songs while singing on five.

Two of them became Top 40 hits, however, leading to a seismic shift in roles for the follow-up.

"By the time we entered the studio in the beginning of 1977 for Livin' on the Fault Line," longtime producer Ted Templeman said in 2020's A Platinum Producer's Life in Music, "the Doobies had begun to become Mike's band."

Co-founder Tom Johnston had taken a step back while on tour before the sessions for Takin' It to the Streets, citing worsening health. The Doobie Brothers replaced him with McDonald, who was recommended by guitarist Jeff "Skunk" Baxter based on previous collaborations with Steely Dan.

McDonald's voice was perfectly suited for the more R&B-inflected era that followed. "The second I heard him open up his mouth, I said, 'Holy shit,'" former bassist Tiran Porter wrote in 2022's Long Train Runnin': Our Story of the Doobie Brothers. "My mind was blown right there."

Warner Bros. released the Johnston-heavy compilation Best of the Doobie Brothers in the meantime, but the musical changes happening around him were quickly diminishing Johnston's role. It wasn't just that McDonald arrived with a host of new ideas for Livin' on the Fault Line. Johnston's fellow co-founder Patrick Simmons had also bought into McDonald's adult-contemporary vibe.

"I wasn't feeling so comfortable musically with the things that were happening," Johnston told Rolling Stone in 1979. "It had nothing to do with personalities. The music was good, definitely respectable, but it was more of a subdued sound. I was used to Little Richard-style R&B and good hard rockin.' I like to be very energetic onstage, and the music didn't lend itself to that. It was incredible writing by Michael but not right for me."

Listen to the Title Track From the Doobie Brothers' 'Livin' on the Fault Line'

Johnston arrived with five songs for consideration on Livin' on the Fault Line. None would appear on the finished product, as Johnston ultimately quit. "I didn't feel like I was adding enough to the band at that point," he told the Los Angeles Times in 2022. "I wasn't comfortable."

Simmons tried to convince Johnston to stay but couldn't. Simmons told Rolling Stone that "Tommy said, 'I'm going to Rio. I'll see you guys later. You go do your thing. Rock 'n' roll means a lot to me, and I feel terrible being around you guys – because I see you cookin' and I ain't doing shit.'"

Suddenly, McDonald and Simmons had a blank canvas, with none of the biker-boogie constraints from the group's early years. They filled it with hushed, jazzy asides.

"I knew this record, which became Livin' on the Fault Line, was going to be different," Simmons said in Long Train Runnin'. "Our boundaries had shifted and so, for me anyway, I kind of let go of more traditional forms and tried to write songs that were a little more experimental. I felt like Jeff and Mike might be able to help with the crazy ideas that had worked their way into my consciousness."

If that sounds a world away from "China Grove," "Black Water" or even the title track from Takin' It to the Streets, that's because it is. The musicianship was uniformly impeccable, but the cerebral mood on Livin' on the Fault Line was too often simply uniform.

"The Doobies were in one of those periods where we would sit around and think about how many chords we could put in a song or how many times we could change keys in a song," McDonald later told Vulture. "The backlash to that was, 'Oh, that's all yacht-rock stuff, we want a purist rock 'n' roll song with two or three chords. Get back to the roots of rock 'n' roll.'"

Listen to the Doobie Brothers' 'You Belong to Me'

Livin' on the Fault Line had no such plans. Released on Aug. 19, 1977, it became a gold-selling Top 10 album on the strength of what came before but was ultimately the first Doobie Brothers release without a Top 40 entry since their roundly ignored self-titled debut.

"You Belong to Me" remained tucked away here until co-writer Carly Simon reworked it into a more radio-ready Top 10 hit the following spring. In a nod to his 21st-century role as a ubiquitous interpreter of Motown classics, McDonald attempted to liven things up with a cover of Marvin Gaye's "Little Darling (I Need You)" – but nothing could break this abiding sense of sleek, over-thought monotony.

"We were experimenting with chords, a lot of complex chord progressions, counter-rhythmic stuff and key changes," McDonald told Vulture. "We enjoyed doing that – and for a while, we even may have gotten a little bit carried away," he added with a laugh.

Still, Simmons remained one of this musical shift's biggest proponents, later calling the title track from Livin' on the Fault Line one of his proudest moments in the Doobie Brothers. "As far as I was concerned, I liked what was happening," he told UCR in 2014. "I liked what had happened before, and I really liked where things were going. I liked Mike’s tunes, I liked his sensibility musically, and I felt comfortable with the music in general."

They just needed to match their undeniable chops with more approachable songs. So much of Livin' on the Fault Line stumbled for want of the required hook.

McDonald delivered on Minute by Minute, the three-times platinum yacht-rock triumph that followed in 1978. "What a Fool Believes," co-written with Kenny Loggins, would become a chart-topping Grammy-winning Song of the Year. Rougher sailing was still ahead, but for a moment this remade lineup's promise was no longer over the next horizon.

"Tommy and Michael, their styles were just so different, but Michael seemed like a breath of fresh air for the Doobies," Loggins told the Times. "Had they only had the Tommy Johnston era — and I love Tommy — they might not have lasted as long as they did. With Michael, they rode the tide of change in pop music."

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