The Doobie Brothers were not only one of the most popular American bands of the ’70s, they were essentially two of the most popular, given the dramatic change to their sound halfway through the decade. The first lineup took shape in the Bay Area in 1970 as the original core of singer and guitarist Tom Johnston, guitarist Patrick Simmons, bassist Dave Shogren, and drummer John Hartman developed an earthy, boogie-friendly blend of rock, country, and R&B. The band’s tight vocal harmonies added a quintessentially SoCal breeziness to “Jesus Is Just Alright With Me”, “Long Train Runnin’,” and the irresistibly nimble “China Grove.” Plagued by ill-health due to burnout, Johnston was absent for much of 1974 (departing two years later), a setback that should’ve ended the party. Instead, The Doobies got a boost by incorporating two musicians set adrift by Steely Dan’s decision to stop touring: guitarist Jeff “Skunk” Baxter and singer/keyboardist Michael McDonald. Now favoring the mix of smooth soul pop and creamy synth splendor found in hits like “What a Fool Believes,” The Doobies enjoyed a second golden age before breaking up in 1982. The brotherhood reformed five years later, striking an affable balance between both incarnations over the tours and studio efforts that followed. And while Johnston was back at the helm, he was often found sharing the stage with his sometime-Doobie counterpart McDonald.