David Rowell is the deputy editor of The Washington Post Magazine.

In March 1971, the Allman Brothers Band was booked for three nights at the Fillmore East theater in New York. The Allmans had produced two studio albums by then, which had done a modest business at best, but through their constant touring they had found believers in their stew of American music — informed by the blues, jazz, country, a hint of gospel, with big slabs of rock. Not many rock bands before the Allmans were equipped with two lead guitarists (or two drummers), but Duane Allman and Dickey Betts’s competitive interplay, not unlike Charlie Parker’s and Miles Davis’s in the heyday of bebop, helped elevate the music to a new plane of harmonic daring. At the end of the third night’s first set, they closed with “Whipping Post,” which Greg Allman sang as if the theater was coming down around him. When they arrived at the song’s end, the band held the last note for what seemed an eternity.

In some ways, it feels like that note never really stopped, since “At Fillmore East” is widely considered to be the greatest live album in rock history. That same sense of resonance is true of much of the music made in 1971. Some of the landmark albums released that year include the Who’s “Who’s Next,” Van Morrison’s “Tupelo Honey,” Neil Young’s “Harvest,” Black Sabbath’s “Masters of Reality,” David Bowie’s “Hunky Dory,” Carole King’s “Tapestry,” Led Zeppelin’s fourth, untitled album, Yes’s “The Yes Album” and “Fragile,” Sly and the Family Stone’s “There’s a Riot Goin’ On,” the Doors’ “L.A. Woman,” the Rolling Stones’ “Sticky Fingers,” the Eagles’ debut album, and Marvin Gaye’s “What’s Going On.” These albums would not only influence future artists but also help shape how we think about popular music today.

As journalist David Hepworth makes clear in “Never a Dull Moment: 1971: The Year That Rock Exploded,” the entire industry was new enough that what it still had to learn — about the power of rock spectacle, the increasing importance of concert tours, the shift of attention from singles to albums or album-oriented rock — was endless. So in terms of sheer subject matter, Hepworth is in fertile territory. His ambition, as he announces it, is arena-size: “This book is a journey through the past to discover what happened that year, in what order, why it did, how the changes on the surface were responding to huge seismic changes underground, how it shaped and was shaped by a few hundred people who were in their midtwenties at the time, and why the music of 1971 still rings so clearly almost fifty years later.”

But on the first page, he blasts a dissonant note when he asserts that the last day of 1970, which saw the Beatles’ official breakup, marked a cataclysmic shift in rock music. “You might say this was the last day of the pop era,” Hepworth writes. “The following day . . . was the first day of the rock era.”

"Never a Dull Moment: 1971 The Year That Rock Exploded" by David Hepworth (Henry Holt)

That is both silly and faulty. Part of the reason “rock exploded” in 1971 goes back to what was happening in the genre years before. When supergroup Cream came on the scene in 1966, when performers such as Simon and Garfunkel and Connie Francis were thriving, it was like a pirate ship laying siege to lesser vessels. The following year the Doors, from Los Angeles, produced a debut album that stomped all over the sunny, strumming sound of California folk-rock with its blues-based, raucous anthems and unnerving lyrics, rounded out by Jim Morrison’s dark oedipal stroll “The End.” Two years later, Jimi Hendrix walked onto the Woodstock stage in the early morning to close out the festival and produced his own rocket’s-red-glare reading of “The Star-Spangled Banner.” As the last dazed hippies wandered off Max Yasgur’s farm, the pop era of the Beach Boys’ “Fun, Fun, Fun” must have felt as long ago as Howdy Doody.

The scope of the book also poses a problem. Wikipedia offers a perfectly full outline of the music created in 1971, in what order, the people who shaped it and what was going on in society. What Wikipedia doesn’t do is make clear why the music still matters. That’s where Hepworth should come in, but too often he misses his cues.

Fortunately, Hepworth offers interesting observations about some of the music from that year, such as “Tapestry.” King’s initial album revolutionized the record business in a few ways: It was the first to sell consistently big numbers month in and month out, making it the first “evergreen” of the rock era. (By 2015, it had sold 25 million copies.) “Tapestry,” he writes, showed the buying power of women, in particular, and by the time King played the Troubadour in Los Angeles, “almost all of them were with their mothers.” Forget the half-tank, half-armadillo on the cover of Emerson, Lake & Palmer’s “Tarkus” or the gnarled old geezers on Jethro Tull’s “Aqualung” and Led Zeppelin’s IV (wait, are those guys brothers?); Hepworth helps you appreciate that the “Tapestry” cover benefited enormously from a dimly lit portrait of a woman in a sweater, crocheting, with a cat by her bare feet — a figure who didn’t look like a musician so much as your cousin from Waukesha. Hepworth digs up an illuminating quote from songwriter Carole Bayer Sager on King’s unique appeal, noting that she had “a voice every woman thinks she could have.”

So much music, so many players. Hepworth re-creates 1971, convincingly, as an ensemble play in which characters are constantly bumping into one another and having life-changing encounters. In this studio is Joni Mitchell, and in the next one over are the Carpenters. Here’s Jackson Browne, taking a break from working on his debut album (with the rhythm section from “Tapestry”) and driving through the Southwest, where inspiration strikes. He writes a song that begins, “I’m standing on a corner in Winslow, Arizona.” That he happened to run the song by his neighbor Glenn Frey, who was starting up his own band, explains why “Take It Easy” landed on the Eagles’ debut album instead. And in a bizarre case of fortuitous luck and potentially deadly circumstances, Deep Purple, who had come to Montreux, Switzerland, to use the Rolling Stones’ mobile recording truck, happened to observe a Frank Zappa and the Mothers of Invention concert going up in flames (reportedly, someone shot a firework at the venue’s ceiling). The members of Deep Purple, who were staying in the hotel that housed the burning casino, watched the smoke drift across Lake Geneva; the bassist, Roger Glover, was inspired to write — wait for it — “Smoke on the Water.”

Hepworth has a sharp appreciation for the rich detail. We learn that when Linda Ronstadt played Disneyland, she was required by contract to wear a bra. Marvin Gaye, at 31 and with no athletic background, wanted to play football for the Detroit Lions. (Hepworth handles that in a few sentences; however, in a hilarious article for ESPN, writer Justin Tinsley tells the full account and quotes Gaye, who bulked up 30 pounds for a tryout, as saying, “I’d rather catch a pass and score a touchdown in Tiger Stadium than rack up another gold record.”) Hepworth spins an intriguing account of the complexities and uncertainties looming over the Concert for Bangledash in August 1971. Fresh from his “All Things Must Pass,” George Harrison was one of the principal figures of the event, but since he hadn’t played the frontman before, and since his last full show with the Beatles was back in 1966, the pressures on him were enormous. Harrison — who enlisted Eric Clapton to join him but worried that his friend, who was badly in the grips of heroin, wouldn’t show up — recruited Peter Frampton as a stand-in without exactly making that clear to Frampton.

These passages make you appreciate the sort of stumbling around and naivete of the era, but they can’t explain the staying power of the music. Instead, where musical insights feel as necessary as sound checks, Hepworth just offers dry ice. The band Yes wanted to make music that went beyond the conventional ideas of what rock could be, bridging the structures of classical music with the harder-hitting aspects of rock, but Hepworth reduces all of that to the simplistic, lazy notion that Yes “craved complexity.” He tells us that what Led Zeppelin IV “said most immediately was, we are not Grand Funk Railroad.” (Okay, but did it say whether they were Three Dog Night?) He also reports that what impressed Led Zeppelin’s young audience was “that this music appeared difficult to play.”

Your head is humming and it won’t go/In case you don’t know.

No kidding!

At the beginning, “Never a Dull Moment” appeared difficult to write. By the end, though, it read as if it were all too easy.

Never a Dull Moment
1971: The Year That Rock Exploded

By David Hepworth

Holt. 307 pp. $30