It’s an August afternoon, deep into the summer of the Grateful Dead, and Aaron Dessner is putting the final touches on his magnum opus. For the past four years, he’s moved steadily down the Steal Your Face rabbit hole as he’s recorded Day of the Dead— a massive, 59-track, multi-band audio re-creation of the Dead’s songbook that will one day also serve as a Nuggets-like Rosetta Stone for early 21st-century independent rock.

Just over a month ago, the Dead’s “core four” members— guitarist Bob Weir, bassist Phil Lesh, and drummers Bill Kreutzmann and Mickey Hart—played their last “Fare Thee Well” shows at Chicago’s Soldier Field, and Deadhead fever is at a temperature it hasn’t reached since Jerry Garcia passed away in 1995. A sitting president went so far as to describe the Dead as a distinctly “American band” in the event’s program, Chicago transformed from “The Jewel of the Midwest” into a citysized Shakedown Street and Dead tributes have popped up everywhere from museums to traditional houses of worship. Bill Murray, Chloë Sevigny, Katy Perry, Sen. Al Franken, George R.R. Martin, Woody Harrelson, Lars Ulrich and Jim Irsay—not to mention enough musicians to field an indie versus jam flag football game—made the pilgrimage for what was billed as the final grouping of the band’s surviving classic members. While it is only somewhat accurate to say that it’s never been a better time to be a Deadhead, it’s definitely never been a better time to come out as a closet Deadhead and wax poetic on the band’s cultural/ personal impact, both onstage and in the media.

On this idyllic afternoon, Aaron’s relaxing with his family on a lakeside hammock outside of their quaint home just north of Hudson, N.Y.—a small, beautiful city on the western border of Columbia County. In recent years, Hudson and the surrounding Upper Hudson Valley have grown into Woodstock-like garden retreats for retired artistic types, expat Brooklynites and others looking to escape the hustle of modern, #Girls New York and the bustle of its current brunch culture. In other words, it’s a great place to prove a theory that all great crate diggers have the potential to grow into expert antiquers or, as Aaron describes, “a little hotbed of important and interesting people.” His young daughter’s school was even founded by two people who met at a New Year’s Eve Dead concert in the late ‘70s.

Aaron has gradually spent more time away from Brooklyn, whose sound and artistic landscape he’s helped map for the past 17 years. However, he’s still close enough to be in earshot of the city’s current happenings and, as he astutely points out, can drive to JFK Airport in less time than it takes to listen to Day of the Dead in its entirety.

He’s also in the process of building a recording space in an old barn and has carved out a second career as an in-demand producer and studio hand for acts like The Lone Bellow, Local Natives and Mumford & Sons, who wrote a portion of their latest record at his Brooklyn home studio and were so moved by their surroundings that they named a song after his neighborhood.

On this sunny afternoon, Bryce—his twin brother, fellow guitarist in indie-rock survivors The National and closest artistic partner—is visiting from his summer home in the Catskills. Wearing cut-off jeans and casual short-sleeved shirts, and with their unkempt-hair inching toward their facial scruff, the Dessners look like distant relatives of the often besuited members of The National—the art-rock collective that, culturally and chronologically, connected The Strokes’ gritty, downtown garage-rock to Vampire Weekend’s Washington Heights, Ivy League indie-Afro-pop, and slow-burned from blogger underdogs opening for Clap Your Hands Say Yeah to one of the most far-reaching New York indie bands of their generation.

Like all great rock combos, each member of the quintet has been assigned a carefully defined, if not entirely all-encompassing, persona: Matt Berninger, The National’s baritone-voiced frontman capable of singing both grand, acceptance-of-age lullabies and screaming angsty rock anthems; Aaron, the group’s in-house producer and chief instrumental songwriter; Bryce, their classical enthusiast and composer-in-residence; Scott Devendorf, the band’s genial skate-punk-hippie bassist; and his younger brother Bryan, the new-wave-influenced drummer who was described in The National film Mistaken For Strangers as the rock-and-roll counterpoint to the rest of the band’s coffee shop ethos.

Though few onlookers would have pointed to the Dead as an obvious influence when they first formed, over the past eight years and especially as they geared up for the release of Day of the Dead, The National have emerged as both unassuming heirs to the Dead’s storied songbook and harbingers of interfaith indie-jam cool.

“Deadicated was well meaning, but I’m not sure how many people really got deeply into that,” Aaron says of the early ‘90s Dead tribute benchmark that drew in unexpected fans like Jane’s Addiction, Elvis Costello, Suzanne Vega, Dwight Yoakam and Lyle Lovett. “We’re shining a light on their songs and songwriting, and then, the avant-garde aspects of the Dead. ‘Inventive reinterpretation’ is a definite theme, but there is a real mixture of sounds, just like the Dead had different periods—some more radically different than others. It doesn’t really matter if the songs were recorded at the same studio or with the same group of people—there’s a thread that ties it all together.”

His brother chimes in instinctively, elaborating on Aaron’s thoughts and demonstrating the sibling telepathy that makes The National’s swells of sound feel so seamless. “There are all these entryways—very well-known artists that are really accessible, music for really serious listeners, which is probably what we’re most proud of, and some crazy avant-garde outliers that really excite me, but maybe not other people. There’ve been lots of heated discussions about the sequencing.”

Bryce is also bouncing between myriad projects, including a curatorial commitment in Europe, film scores and a ballet that challenges all conceptions of how the word “heady” should be used in an article on the Dead. Day of the Dead stems from Aaron’s longstanding relationship with Red Hot, the not-for-profit dedicated to fighting AIDS through pop culture and eye-opening allstar albums. Yet, like most of the Dessners’ projects, they are both deeply involved. It’s their most ambitious endeavor since “Dark Was the Night,” a Red Hot compilation and subsequent concert that featured contributions from David Byrne, St. Vincent, Bon Iver, Yeasayer, Sharon Jones and many others. If it’s not their Chinese Democracy, then Day of the Dead is definitely the final piece of the Berlin Wall to fall between the great divide that once separated indie from jam.

There’s at least a festival’s worth of small victories planted throughout the album—which will be available as an expansive vinyl box set when it’s released in late May—whether it’s an official version of The War on Drugs’ “Touch of Grey” cover, Jim James’ destined reading of “Candyman,” a Kevin Baconlike meeting of Kurt Vile and J Mascis on “Box of Rain” or the inevitable pairing of Justin Vernon with his sweet-voiced, cosmic godfather Bruce Hornsby on “Black Muddy River.” Charles Bradley turns in an Apolloworthy “Cumberland Blues,” while Courtney Barnett adds some Pavement-like slackerswagger to the Altamont response “New Speedway Boogie.” Arcade Fire multiinstrumentalist and folk enthusiast Richard Reed Parry rubs elbows with The Band’s Garth Hudson, Caroline Shaw and Little Scream on “Brokedown Palace;” Jenny Lewis offers both a sweet reading of “Cassidy” with Moses Sumney and a sultry take on “Sugaree” with Phosphorescent; and Weir shows up on the album’s two live tracks, Wilco’s 2013 version of “St. Stephen” and the album-closing “I Know You Rider” with The National.

“Wilco is in the bag that the Dead were—as much as I don’t get from their records, I get from their live performances,” Weir says. “I’d always heard: ‘You’ve got to hear this band Wilco. They kind of remind me of you guys.’ When I finally heard them live, I was blinded. They play off of each other and they get the songs. When they’re playing, everybody in their band knows every word of that story. You can hear everybody watching the movie in their music.”

In what could surely play out like a Pretty Woman situation for hippies scorned by pasty-skinned record store clerks in the ‘90s, a holy trinity of Matador acts lend their support to some of the album’s most psychedelic nuggets. Sonic Youth’s chief jamband ambassador Lee Ranaldo revisits “Mountains of the Moon” with Lisa Hannigan and other friends, Ira Kaplan brings Yo La Tengo’s hushed beauty to “Wharf Rat” and, speaking of Pavement, Stephen Malkmus & The Jicks offer a full-on segue between foster siblings “China Cat Sunflower” and “I Know You Rider.”

Aaron divided the album into three sections in line with the Dead’s motifs: “Thunder,” “Lightning” and “Sunshine.” The entire collection flows like an extended Dead show that moves from first-set songs, like the above-mentioned “Touch of Grey” and “Candyman,” to a mammoth, 16-minute “Terrapin Station,” crafted with the help of a few members of Grizzly Bear; “drums” and “space” segments courtesy of So Percussion, Man Forever and Oneida; and Sam Amidon & Friends’ Seeger-inspired version of the traditional goodbye hymn “And We Bid You Goodnight.” Cass McCombs and his collaborators, including Furthur drummer and post-jam pioneer Joe Russo, lay down a crazy “Dark Star” that morphs into a second, experimental track labeled after a lyric as “Nightfall of Diamonds.” For his contribution, McCombs says he set up a show “for the purpose of just doing one song—‘Dark Star’—and, when we got into the studio, cut in and out of the shit we did onstage, Anthem of the Sun style.” The Flaming Lips also offer a second, twisted reading of “Dark Side,” one of the Dead’s signature songs, while Real Estate finds a Byrdslike breeze on “Here Comes Sunshine,” recorded with Woods’ Jarvis Taveniere. Closing another circle, Mumford & Sons’ rocking version of “Friend of the Devil” feels stylistically akin to their surprisingly plugged-in latest record, which was partially inspired by their time with Aaron.

In order to tie Day of the Dead‘s various threads together, the Dessners also assembled a house band featuring Aaron, the Devendorfs, The Walkmen’s Walter Martin, former Yellowbirds members Josh Kaufman and Sam Cohen, and Takka Takka drummer Conrad Doucette to back many of their guests and allow for full-blown improvisation. Bryce participated in some of the sessions and wrote a new piece of orchestral music as a prelude to “Terrapin Station,” which includes a few Easter eggs itself. “There’s an ‘Other One’ quote in there since we didn’t record a version for the record,” he says.

Scott likens the house band’s sessions to the loose feel of The Basement Tapes. “It was interesting and educational to record with that intention,” he says over a beer at Threes Brewing, a Brooklyn bar and venue where he hosts a monthly Grateful Dead DJ set that, on this evening, kicks in with some primal, blues-boogie Pigpen chestnuts. Perhaps The National’s most approachable member as well as the band’s resident cross-genre record collector, Scott’s a true Dead freak, who occasionally wears bootleg Stealie T-shirts onstage and even had the LivePhish app on his phone for a while. “We didn’t always know who was going to sing and, sometimes, ideas came out of nowhere— bang, bang, bang. Other times, we channeled a National vibe. ”

“This project has been like coming home to all this music that we listened to when we were at camp,” Aaron says. “When we were sitting out in the woods and getting good at guitar, 80 percent of what we played was the Grateful Dead. What’s especially interesting about this record is that there aren’t just some of the great voices of our generation, but also the generation above us and just below us. It is just really fun to hear their passion, hear them celebrate the music and shine a very positive light on the songwriting—the soul of it. The Dead are now just part of the canon of American music.”

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