If you didn’t realize Deerhunter have a new release out, that’s kind of the point. A proper follow-up to 2015’s vibrant Fading Frontier is still in the works, but Double Dream of Spring is available on cassette, and that’s it. No vinyl. No streaming services. Not, by the looks of it, even a digital leak. The mostly instrumental, 40-minute tape was supposed to be on sale throughout the band’s current tour, but it sold out on the first night. The only way to hear the music was to wait in line and buy one of 300 copies at the inaugural Brooklyn show. The result, as anachronistic in content as in its format, arrives right on time.

It’s here and then it’s not. It’s vanishingly limited and—in theory, in a world of digital rips and frictionless file-sharing—infinitely available to whatever audience might be interested. Frontman Bradford Cox said the music was released on tape because of the long lead times for vinyl coupled with the flood of content that has diminished the rationale for giving away music online. He was regretful about how insanely fast the tapes sold out and said he couldn’t comment about plans for a repressing. Because the music here is (almost) all original material recorded with the full Deerhunter lineup (Cox, drummer Moses Archuleta, guitarist Lockett Pundt, bassist Josh McKay, and keyboardist Javier Morales) in their home base of Atlanta, this outing feels more substantial than most of the Deerhunter family’s other non-album releases, from a John Peel tribute tape to bedroom-recorded blog freebies.

The resulting album feels spontaneous yet brimming with ideas. It’s also a bit of a left turn: The tape tries on passions both old (krautrock jams) and new (a harpsichord). In that spirit, Double Dream of Spring is an engrossing if endearingly scraggly excursion into the avant-garde, a great, minor work from a great, major band.

Side A, which is wordless, sounds as much like spring as can be expected from a band who even managed to turn a Diplo remix into something dreadful and morbid. The warped bird calls of opener “Clorox Creek Chorus” quickly give way to standout “Dial’s Metal Patterns,” a latticework of woodwinds, keys, and clip-clop percussion that sprawls out for the next dozen-ish minutes, like Stereolab building a clock in Atlanta outsider artist Lonnie Holley’s backyard art studio. The side closes with “Strang’s Glacier,” a giddy reverie built around piano bass notes, splashing cymbals, and ethereal sighs that storm up like an eerie portent from the band’s clamorous 2007 breakout album, Cryptograms.

Side B, which has some words, is only a bit less wayward. The stately piano instrumental “The Primitive Baptists” sets up the tape’s first song with proper vocals, “Denim Opera,” and after so much build-up, it’s a thrill to hear frontman Bradford Cox belt out the rallying-cry charge, or yelp a high note on the word “believe,” singing a song about crimes and salvation. The track’s lo-fi clatter wouldn’t have been out of place on Deerhunter’s bountiful 2008 disc Weird Era Cont. Listening to this song, it’s hard to tell whether to fix a serious face or burst out laughing, and that feels purposeful.

After a couple of instrumentals that feature the buzzing of a cord being plugged into an amp and a plinking marimba, Deerhunter save their most powerful revelation for the finale: a faithful take on composer Charles Ives’ sparse 1919 masterpiece “Serenity,” with lyrics by Quaker poet John Greenleaf Whittier. By the end of this whole bemusing, Wonka’s boat ride of a collection, a song that Ives himself once damned as “nice” sounds a bit like an amen, or at least a bittersweet Benadryl equivalent.

Its title nods to both a hermetic 1970 book by the poet John Ashbery and that text’s namesake, a 1915 trompe l’oeil painting by Italian surrealist Giorgio de Chirico. These references are fair warning that we’re entering an erudite, uncanny conversation: a weird era that continues because it’s passed down between artists like folk culture. Just as relevant, though, is the “doubles” conceit, which Deerhunter neatly apply to the two-sided structure of a cassette.

Cox has said Deerhunter’s upcoming, Cate Le Bon-produced full-length will carry the working title Why Hasn’t Everything Already Disappeared?, which, strikingly enough, is also the name of one of the final essays the French philosopher Jean Baudrillard wrote before he died in 2007. “Behind every image,” Baudrillard said, “something has disappeared. And that is the source of its fascination.” Double Dream of Spring is a boutique tape that most of us will only ever encounter as ones and zeroes, and for as far as that goes—whether until the next Deerhunter record, or beyond—it’s fascinating. Ephemeral though it may be, it’s also an achievement to celebrate. Even, or especially if, as Baudrillard would have it, we must ask: “Is it, in fact, the real we worship, or its disappearance?”