In retrospect, the second Doobie Brothers album sounds like an amalgamation of all early-‘70s rock styles. Toulouse Street combines the breezy acoustic sheen of the Eagles (“Listen to the Music”), the revved-up grit of Creedence Clearwater Revival (“Rockin’ Down the Highway”), and the honeyed, jazz-inflected jams of the Allman Brothers (“Mamaloi”). In addition, group leaders Tom Johnston and Patrick Simmons had a great affinity for the singer-songwriter movement epitomized by artists like James Taylor. Among the album’s best songs are “Toulouse Street,” “White Sun” and “Snake Man,” three pared-down acoustic performances. Few bands from this era were as adept as weaving together strands of folk, gospel and hard rock, but the secret ingredient in Toulouse Street is the subtle shades of R&B. While the Doobies were never considered a funk ensemble, songs like “Cotton Mouth” are elevated by the rhythmic interplay between bassist Tiran Porter and dueling percussionists John Hartman and Michael Hossack. Johnston and Simmons made these songs shine, but the rhythm section is what makes them move.