The Beach Boys weren't in the best place as the '60s drew to a close. In addition to being labeled an out-of-touch relic by the new generation of acid-dosed hippies, the band was going through an identity crisis as it struggled to rebalance in the wake of leader Brian Wilson's mental exhaustion following the abandoned Smile project.

And then there was the very real claim that the Beach Boys were part of an earlier era that thrived before the Beatles, the Rolling Stones and Jimi Hendrix shook everything up and rendered the group's choirboy harmonies and clean-cut image totally square. No matter that their Sgt. Pepper-influencing masterpiece Pet Sounds was just a few years old and they'd logged one of the biggest hit of their career, "Good Vibrations," around the same time.

At least that was the going line at the end of the '60s. But a closer look reveals something entirely different: The Beach Boys were not only still relevant, they were making some of the best music of their career as Wilson skidded to a crashing halt after Smile became DOA amid prolonged and morale-deflating sessions. Smiley Smile, which picked up the pieces of its similarly named album, and the R&B-inspired Wild Honey were released within three months of each other in late 1967 and are among the best back-to-back records in their deep catalog.

Even better are the two albums that were released almost exactly a year apart at the top of the new decade: 1970's Sunflower and 1971's Surf's Up. Together they set the stage for Feel Flows: The Sunflower and Surf’s Up Sessions 1969-1971, an extensive box set that collects 135 tracks, 108 of them previously unreleased, over five discs.

It was a productive period for the group. Even after Smile was aborted, the Beach Boys wasted little time recording and releasing new music. They put out four albums – two of them in 1967, the year Wilson gave up on his masterwork – before the decade was over. Remnants of Smile were scattered over those releases, but for the most part these were freshly composed songs, with everyone chipping in to make up for Wilson's increasing absence.

As such, Sunflower and Surf's Up were the most democratized Beach Boys albums up to that point. All six members receive cowriting and lead-vocal credits on the former, and the latter is pretty much dominated by the other members until Brian Wilson's concluding trio of songs. The outtakes, alternate versions and live tracks gathered on Feel Flows emphasize their contributions while also making sure Wilson isn't too far from the spotlight.

The best songs from this time – "Tears in the Morning" (Sunflower), "Long Promised Road," "Feel Flows," "'Til I Die," "Surf's Up" (Surf's Up), the 1969 single "Break Away" – combine sentimental nods to their storied past with an eagerness to move on from it. Within the context of this box, they sound like parts of a more earnest attempt to distinguish the group in the new decade.

There aren't too many rough patches in the journey. Unreleased songs "Big Sur" and "Sweet and Bitter" don't need much polishing to fit on Surf's Up, and a live version of "Susie Cincinnati" from 1976 sets up the band's '80s resurgence as a popular live act. Not so good are the Halloween goof "My Solution" (with Brian Wilson attempting a Vincent Price accent over cheesy background sounds) and the Beach Boys' limp take on "Seasons in the Sun" produced by Terry Jacks, who later had a No. 1 hit with the soft-pop song in 1973.

Like other recent period-specific compilations – including 1967 - Sunshine Tomorrow, the best of them – Feel Flows: The Sunflower and Surf’s Up Sessions 1969-1971 is loaded with backing tracks, a cappella versions and alternate takes of the albums' songs, as well as new mixes of some of the singles and leftovers that have surfaced on other projects over the decades. Nothing here will attract listeners who think the Beach Boys faded into irrelevance after the mid-'60s, but fans will discover plenty of exceptional and unheard tracks from one of their most fertile and productive runs.

After this things got sketchier: The music became spottier, Brian Wilson's mental facilities deteriorated even further and the Beach Boys' creative streak, which surfaced one final time on 1973's Holland, gave way to wan nostalgia. But as the '60s turned toward the '70s, there was still something to prove to themselves, as well as to the new breed of music fans. Feel Flows soundly confirms their standing as one of the era's all-time greats.

Beach Boys Albums Ranked

There's way more to the band that surfing, cars and girls.

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