For much of my youth and young adulthood, I listened to music for cheap emotional catharsis, and so I preferred songs that were feral, tenuous, unstudied, and impolite—anything that sounded as mixed-up and precarious as I usually felt. I equated wildness with authenticity, and wanted only to be reminded, again and again, that I wasn’t alone or unique in my feelings. This isn’t a particularly unusual way to commune with records, though it is, perhaps, the easiest way. I eventually came to understand that over-valuing anguish and ecstasy—conflating theatrics with feeling, and feeling with Art—was limiting and naïve. Things like pleasure, contentedness, a solid laugh—any good, ordinary moment—are just as evanescent, and certainly just as formidable (and important) to capture.

Beginning in the early 1970s, Steely Dan—the duo of Walter Becker and Donald Fagen—made cerebral, clever, formally sophisticated music that resisted any autobiographical extrapolating. Even in the context of the era—the late 1960s had seen the development and rise of both jazz-fusion and prog-rock, two of the brainiest, chops-iest genres going—their work was shrouded in irony and a distancing intellect. There was no pretense of dissolution or even emotion. Listening to their records felt like running my hands along a slab of polished marble—there were no craggy bits to grab on to, no easy way to find purchase—and so for years, I believed that Steely Dan’s seeming aversion to sincerity meant that they were cold and dorky. Did they not just make inert, polished music for men with meticulously groomed facial hair?

Then Aja—Steely Dan’s sixth album, from 1977—turned everything around for me: It’s a thoroughly convincing argument against my notion that aggressive or discordant music was inherently real and rebellious, whereas virtuosic or studied songs were always limp and bloodless. Aja is as bold as records get. It’s full of strange, unprecedented, disorienting moves. It is braver, more idiosyncratic, and more personal, in some ways, than any other record I own.

Aja is as much a jazz record as a pop one, though in its best moments, it’s both and neither. Steely Dan were so expert at fusing genres it’s often hard to say what bit came from where, or exactly which tradition (fusion, R&B, soul, disco, classical) was being mined or reimagined. Because these songs were rendered so seamlessly, it’s easy to overlook how brazen they were. Aja is like driving down a treacherous, cliff-side road in the most luxurious car ever made: If you sink deep enough into that supple leather seat, it is possible to forget entirely about the twists and turns, the threat of looming destruction. It’s possible to forget about gravity entirely.

Steely Dan is generally associated with Los Angeles, where they made most of their records, but Becker and Fagen are both New Yorkers (Becker was born in Queens; Fagen was born in suburban Passaic, New Jersey), and their sensibilities were plainly shaped by a kind of wry, East Coast cynicism. It manifests most palpably in Aja’s lyrics, which are funny, surreal, and, for the most part, narratively ambiguous. On a song like “Deacon Blues,” which they co-wrote, it’s impossible to deny the precision of their phrasing, and the unexpected depth of the song’s sentiment:

Learn to work the saxophone

I play just what I feel

Drink Scotch whiskey all night long

And die behind the wheel

They got a name for the winners in the world

I want a name when I lose

They call Alabama the Crimson Tide

Call me Deacon Blues

Becker later said the song was about the “mythic loserdom” of being a professional musician—how glorious it might look from the outside, how grueling it is in practice. “Deacon Blues” is a fantasy of art-making, spun by someone who has never had to do the work, and therefore requires a funny sort of narrative distance: Becker and Fagen were looking at their own lives from the perspective of someone who wants what they’ve got, but also someone who fundamentally misunderstands the costs.

Aja produced three excellent singles (“Peg,” “Josie,” and “Deacon Blues”) and sold millions of copies, becoming the group’s most commercially successful release. But it was a perplexing bestseller. Steely Dan spent the 1970s getting progressively more esoteric: jazzier, groovier, weirder. Even now, mapping the album’s melodic and harmonic shifts is impossible to do with confidence. Its songs are sprawling and fussy, populated by oddball characters with inscrutable backstories, like “Josie,” from the song of the same name (“She’s the raw flame, the live wire/She prays like a Roman with her eyes on fire”) or “Peg,” an aspiring actress headed who-knows-where, who’s “done up in blueprint blue.” “Blueprint blue”! It’s the kind of simple, perfect description prose writers pinch themselves over.

Outside of the studio, Becker and Fagen reveled in being a little rascally. They took long breaks from touring, and when they conceded to an interview, they often appeared self-satisfied, if not antagonistic. Their disdain for the record business occasionally bled into a disdain for their fans, itself a kind of merciless, punk-rock pose. When they did tour—like, say, in 1993, when, after a decade-long hiatus, they booked a few weeks of U.S. dates—they did not pretend to enjoy it. That year, when a reporter from The Los Angeles Times asked Becker how the tour was going, he said, “Well, not too good. It turns out that show business isn’t really in my blood anyway, and I’m looking forward to getting back to working on my car.”

Because the production on Aja is so expert—whole stretches are perfect, impenetrable, like the first 31 seconds of “Black Cow,” when that creeping bass line cedes passage to guitar and electric piano, and the backing vocals pipe up for “You were high!”—it’s easy to ignore the sophistication of its architecture. Becker and Fagen used obscure chords (like the mu major, a major triad with an added 2 or 9) and custom-built their own equipment (for 1980’s Gaucho, they paid $150,000 to build a bespoke drum machine). What they were doing was so particular and new, it was often difficult for critics to even find a vocabulary to describe it. On the title track, the verse shifts and dissolves as Fagen croons, “I run to you.” His voice thins as he finishes the line, a little gasp of tenderness. The minute-long drum solo that closes “Aja,” performed by the virtuosic session man Steve Gadd, is dressed with horns and synthesizers, and makes a person briefly feel as if they are being transported to a different dimension. Steely Dan reveled in making technical choices that would have hobbled a less ambitious outfit. That they succeeded still feels like some kind of black magic.

By 1977, it is possible that some corners of the culture had become desperate for music that was intellectually challenging but not exactly arduous to consume—something less predictable than Top 40, but not quite as hyperbolic or gnashing as punk. By the end of the 1960s, rock had been relentlessly and breathlessly defined as a frantic, bloody, all-consuming practice, for both performers and fans. Aja, though, doesn’t necessarily require any sort of deep emotional entanglement or vulnerability from its listeners. In that way, the record works as an unexpected balm, a break—a little bit of pleasure just for pleasure’s sake.

In 1977, on the day Aja was released, Cameron Crowe interviewed Becker and Fagan for Rolling Stone. Predictably, they were bemused by his questions. Becker told Crowe that they spent most of their time writing, recording, and obsessively tinkering. “We overdubbed a lot of the overdubs over,” he said. By then, whenever Steely Dan decamped to the studio, they hired a cabal of professional musicians—more than 40 are listed in the credits to Aja—and ran the sessions themselves, with militaristic precision. Becker and Fagen seemed to savor the idea that Steely Dan might be mischaracterized, in print, as something as pedestrian and ordinary as a band. “You can get studio musicians to sound exactly like a rock and roll band,” Fagen said. It’s obvious what he meant. They’d pulled one over on us, again.