It was 50 years ago today, give or take, that the Beatles inaugurated the Summer of Love. On June 1, 1967, a newly mustachioed Fab Four released Sgt. Pepper’s Lonely Heart’s Club Band, and in a matter of hours, its songs were everywhere (for example, Jimi Hendrix famously covered the title track at his London show on June 4). As we embark, tetchy and stressed, upon what seems to be a Summer of Hate, it’s tempting to soothe our raw nerves with nostalgia from bygone innocent ages. While the album is actually quite a bit darker and more death-obsessed than you remember—and functioned, in its own way, as a nostalgic balm during its own era—the 50th anniversary re-release of Sgt. Pepper comes out today, eagerly awaited by Beatle nuts and older listeners who still pay for physical product amid their general confusion at today’s pop landscape. Fortunately, the sumptuous deluxe edition is a carefully considered exercise in Beatles scholarship that ducks most suggestions of revisionist history. It’s not essential, but it is fun.

The deluxe six-disc box is also a crash course on the craft of ’60s-era four-track recording technology, a thorough document of how careful, skilled use of relatively primitive equipment resulted in the most ambitious album recorded at that time. The box includes the original 1967 mono mix augmented with shiny new stereo and 5.1 surround mixes from producer George Martin’s son Giles Martin, plus two discs of rough versions and alternate takes, with a wow-inducing hardcover book and fancy 3D lenticular slipcase to gussy up your bookshelf. (Other, less expensive configurations are for sale, including a two-CD version—also now on streaming services—and a double vinyl release.)

Fanatics will be elated by the clarity of the new stereo mix, which used computers to peel apart the multi-track tapes and punch up the sound in every direction (the 5.1 mix is fun but inessential, like a holographic version of the Mona Lisa). Purists will be suspicious of the new mix’s varied results, as it breathes marvelous new life into songs like “Fixing a Hole” and “She’s Leaving Home,” but turns “Being for the Benefit of Mr. Kite!” into a seismic boom and does zero favors for “A Day in the Life,” which already existed as a perfect recording. Audiophiles will be dissatisfied (as they always are and ever will be) by a surprisingly smushed mastering job on the CD itself (it will sound great on streaming services and positively excellent on vinyl). And the rest of us will wonder what all the fuss is about and go back to our perfectly fine existing copies of the album.

© Apple Corps Ltd.

But the box is a real treat for process nerds with cash to burn. My own Beatles fandom kicked into overdrive when, barely a teenager, I checked out an oversized book from the library called The Complete Beatles Recording Sessions. I had my mind blown by Mark Lewisohn’s definitive book, reading about mysterious alchemic processes like “bouncedown mixes,” “direct injection,” and “artificial double-tracking.” The four Beatles, along with George Martin and EMI Studio’s lab-coat-wearing engineers, used these tricks to make the familiar yet otherworldly noises on those Beatles records I liked so much. Immediately, doors of perception opened before me. I learned where that banshee-seagull sound on “Tomorrow Never Knows” came from. I discovered the chilling Shakespearean dialogue at the end of “I Am the Walrus” was sourced from a BBC Radio broadcast that they plugged, live, into the board during the session. Most impressively, I was informed that “Strawberry Fields Forever” came from two wildly different versions of the song that were recorded separately, then pasted together seamlessly at the track’s one-minute mark.

Although it’s not on the album proper, “Strawberry Fields Forever” perfectly encapsulates the philosophy behind Sgt. Pepper’s Lonely Hearts Club Band. John Lennon’s nostalgic and surreal composition was the first song the Beatles attempted at recording sessions for the album; it and companion piece “Penny Lane” appear in multiple guises in this new re-release, functioning as both a signpost for Pepper and a distillation of its essence. “Strawberry Fields” is filled with special effects—cymbals recorded backwards, phrases played on exotic instruments like swarmandal and mellotron, a false fade-out that fades back in again. And the shimmering underwater piano that drives “Penny Lane” was not a single take but four keyboards overdubbed and mashed together into a unified but hitherto unheard sound. Every crazy idea was explored, and every piece of EMI’s recording gear was put to the test.

As wonderfully as the “Strawberry Fields Forever”/“Penny Lane” single works in the abbreviated two-song format, it could be argued that Sgt. Pepper’s 40 minutes are relatively indulgent and flabby in comparison, a showcase of some of the Beatles’ worst tendencies. There’s Lennon’s acid-burnout laziness masquerading as whimsy (“Being for the Benefit of Mr. Kite!” took its lyrics wholesale from an antique poster in Lennon’s home—a reproduction of the poster is included in the box), alongside Paul McCartney at his most obnoxiously chipper (“When I’m Sixty-Four,”), plus George Harrison’s obtuse exploration of weird-sounding Indian music (the five-minute “Within You Without You”).

This argument doesn’t really hold water, though. While not a perfect album, Sgt. Pepper’s overarching ambition elevates even its weakest moments. (And Harrison’s gorgeous “Within You Without You,” particularly in its newly remixed form, is dark-horse contender for the album’s best track.) As conceived by McCartney during a plane flight, Sgt. Pepper was a vaudeville psychedelic dream, encompassing Britain’s music-hall roots, Victorian and Edwardian imagery, wild new avant-garde ideas, and Pet Sounds-inspired orchestral longing. It was a direct retreat from the commercial sound of teenybopper hits like “I Want to Hold Your Hand” and “She Loves You,” while embracing the new horizons revealed by acid, pot, and London’s underground art scene.

© Apple Corps Ltd.

The 50th anniversary edition’s lavish, over-the-top presentation manages to inflate the album beyond its already mythic status. Amazingly, the bubble doesn’t burst. Sgt. Pepper has been called many things: the greatest album of all time (it isn’t), the first-ever concept album (it wasn’t), the album that pointed the way towards rock’s serious, legitimate future (it didn’t), and the time capsule future generations need to absorb in order to, like, really understand the ’60s, man (they needn’t). Sgt. Pepper is, however, a mile marker for the full-length record album as medium. The Beatles had made several albums before it, but having just retired from touring, they made this one with no deadline and no worry of reproducing it live. They took all the time they wanted and all the money at their record label’s disposal to make it. The finished product was 12-inch vinyl record as art piece, complete with an extravagant cover photo of saints, movie stars, artists, and philosophers; a lavish gatefold jacket with lyrics for every song on the back; and a runout groove at the end of Side Two, containing hidden bonus art (in this case, an endlessly looping piece of screaming gibberish that breaks the spell cast by that impossibly long, haunting final chord of “A Day in the Life”). Sgt. Pepper was always meant to be larger than life. What this 50th anniversary deluxe edition shows, marvelously well, is why it deserves all the extra room it requires.

It wasn’t the songs, necessarily—the Beatles wrote plenty of better ones, before and after. It wasn’t George Martin’s candy-colored production, which instantly date it to 1967, unlike moments of Revolver and Abbey Road, which still sound positively futuristic. It wasn’t even the central concept, which was pretty baggy to begin with—a fictitious band performs a concert with various songs coming from different guests (Billy Shears, ladies and gentlemen).

But this brings me back to that wonderful library book, The Complete Beatles Recording Sessions. In it, Lewisohn diagrams out each rhythm track, overdub, and studio trick that went into making Sgt. Pepper. These processes are outlined in the box set’s own book as well (as well as a great essay on 1967 from record producer Joe Boyd, a retelling of a passage from his masterful, must-read memoir). The two discs of rough takes and mixes are a peek behind the wizard curtain, a glimpse at how Martin and the Beatles ended up with the final product. For all its musical shortcomings, Sgt. Pepper is a triumph of ideas and ambition, a statement of supreme confidence from its authors and peerless competence from its producer and engineers. At times, the album’s a wild mishmash—listen to how loose “Lovely Rita” gets in its final bars, or how the verse and chorus of “Lucy in the Sky with Diamonds” are crudely pasted together with four smacks of a drum—but its sum has always been larger than its parts.

All the alternate tracks and remixed audio ultimately prove that every decision that went into making Sgt. Pepper was the correct one. Among the myriad rough early versions are no lost gems, no mind-blowing discarded vocal takes, not even a hitherto-unreleased song. Aside from “Strawberry Fields Forever” and “Penny Lane,” the only other non-album track from the sessions, “Only a Northern Song,” doesn’t appear here in any version at all, which seems like an oversight for an otherwise comprehensive package.

But if you’re happy with your Pepper already, is it worth buying the new one? Fanatics and trainspotters aside, I’m not sure if many will really notice the differences in the new mix. Ringo’s drums sound great, but they always sounded pretty great to me. McCartney’s bass, bumped to the fore, is supremely melodic, but it sounds slightly less integrated here than it did in the original.

And yet I find myself appreciating songs I’d never particularly cared for, specifically “Fixing a Hole,” which sounds a bit rowdier and thumpier in the new version, and “She’s Leaving Home,” in which the tape is sped up to match the mono mix and make the song a little more light on its feet. I’m also incredulous at how Sgt. Pepper’s loose ends were made—with some crossfading between the individual tracks, another pioneering move on Pepper’s part—into a unified whole. When the orchestra groans, lurches, swoops to that final, crashing chord of “A Day in the Life,” it does, indeed, feel like the miniature Alice in Wonderland world we’d entered 40 minutes earlier has swollen to life-size and gobbled us up. It’s still a trip worth taking.

© Apple Corps Ltd.