The press release began: “Columbia Masterworks’ recording director and his engineering colleagues are sympathetic veterans who accept as perfectly natural all artists’ studio rituals, foibles, or fancies. But even these hardy souls were surprised by the arrival of young Canadian pianist Glenn Gould and his ‘recording equipment’ for his first Columbia sessions. … It was a balmy June day, but Gould arrived in a coat, beret, muffler and gloves.” The rest of the bulletin detailed the other peculiarities that Gould had brought along with him when recording J.S. Bach’s Goldberg Variations for the label.

These were many. Instead of nobly holding his head high with a proper recitalist’s posture, Gould’s modified piano bench allowed him to get his face right near the keys, where he would proceed to hum audibly while playing. He soaked his arms in hot water for up to 20 minutes before takes and brought a wide variety of pills. He also brought his own bottles of water, which, for 1955, was still something that seemed like only Howard Hughes would do. It was these initial, broadly trumpeted peculiarities that helped shape the Gould myth throughout his too-short life, the audacious genius who slightly unsettled everyone around him. Fittingly, throughout the 20th century, there would be no more audacious and initially unsettling act of musical reinterpretation than Gould’s debut studio recording.

With his 1955 recording of Bach’s Goldberg Variations, the young pianist made a compelling case for a work that, at the time, was considered an obscure keyboard composition by an otherwise imposing master of Baroque music. Gould made his counter-argument for the piece’s rightful prominence by taking wild liberties with the source. In addition to playing the work on a piano instead of on the 18th-century era-appropriate harpsichord, Gould rushed tempos and varied his attack with aggression. His body flailed up and down his creaky chair, displaying melodramatic physical gestures—the very cliche of a young genius at work. But instead of seeming like an impudent youngster, Gould’s innovations signaled a clear love for the source material. He took the piece’s unusual status—a theme-and-variation work so varied that it could be hard for a lay audience to follow—and realized that it could be performed with modernist vigor, full of wild twists of character.

Gould drilled his famous technique over time, using an obscure practice known as “finger tapping” to produce muscle memory in his fingers—thereby allowing for dizzying flurries of notes with astonishing control and minimal physical exertion. And at a time when the future members of the Beatles were still obsessing over British skiffle bands, Gould was pioneering the use of the studio as an instrument by splicing together different takes: finding startling collisions of mood that could help drive his conception of a work.

In its fervor for relating Gould’s peculiar behaviors, Columbia’s first press release neglected to mention all the substantive ways in which the pianist was revolutionizing the art of interpretation. The critics, however, did notice. Gould’s Goldbergs received a raft of rave reviews from the New York Times, Newsweek, and Musical America, among others. Even writers who were unsure if his was a respectable way to approach Bach’s sublime music counted themselves impressed by Gould’s array of approaches—including his dancing sprightliness, a dashing top-gear of speed, and swooning sense of drama. And Gould proved a forceful advocate for his own ideas about the piece.

In erudite liner notes that accompanied the first LP issue in 1956, Gould writes about the strangeness of Bach’s theme-and-variation work: “...one might justifiably expect that … the principal pursuit of the variations would be the illumination of the motivic facets within the melodic complex of the Aria theme. However such is not the case, for the thematic substance, a docile but richly embellished soprano line, possesses an intrinsic homogeneity which bequeaths nothing to posterity and which, so far as motivic representation is concerned, is totally forgotten during the 30 variations.”

It’s a fascinating read of the piece—even if it seems trollish to accuse Bach’s Aria for adding “nothing to posterity.” (At least Gould was consistent in his dislike of obvious, top-line melodies. He didn’t much care for Italian opera, either.) Still, it’s true that the power associated with the culmination of Gould's Goldbergs—when the Aria returns—has something to do with how far the listener has traveled since the opening. If you want to make that Aria really floor people at the end, why not blow out the contrasts between the variations as you play them?

Gould makes an argument for his own radical vision of how the piece should be played. He sees his own jagged cadence not in defiance of but as a requisite to Bach’s score. Even listeners who put the Goldbergs on as background music are likely to sit up and pay attention when Gould pours it on during Variation No. 5. With that one far edge of intensity established, his ruminative way of handling Bach’s “Canons” is far more seductive. Gould’s lightning-fast runs tend to get all the press, but they cast into sharp relief his poetic handling of the so-called “black pearl” Variation No. 25. The power of Gould’s 1955 Goldbergs comes from the contrasts that Gould chooses to emphasize.

Gould’s first version of the Goldbergs reportedly sold 40,000 copies in its first five years: A considerable amount for any classical recording at any time, but particularly notable at the dawn of the LP era. The pop-cultural primacy of Gould’s first take on the Goldbergs also fostered some detractors, among them some Bach specialists like Wanda Landowska who were also interested in rescuing the piece from its relative obscurity. Late in life, Gould joined their ranks, offering some withering criticisms of his 1955 recording. In 1981, the pianist told the critic and biographer Tim Page that the 1955 handling of the “black pearl” variation had become particularly unwelcome to his own ears: “It seems to say—Please Take Note: This Is Tragedy. You know, it just doesn’t have the dignity to bear its suffering with a hint of quiet resignation.”

The idea of judging his famous 1955 recording on the basis of those criteria seems like a category error—or a set-up destined to prompt a negative assessment of his first record. The latter possibility is at least plausible, since when Gould offered this self-criticism to Page, he was doing so as part of a new publicity campaign. After being so closely identified with the Goldbergs for decades, Gould had made the rare decision to re-record a work already in his repertoire.

His 1981 recording of the Goldberg Variations is still recognizable as Gould: the strutting precision and emphasis on counterpoint apparent. So too is Gould’s famously divisive practice of humming along with his playing (a natural trait of Gould’s that seemed to flower into a deliberate affectation sometime between 1955 and 1981). But in the interim, much else has changed. There’s less swing in Gould’s playing; even when he turns up the tempi, it feels considered and autumnal.

Variation No. 5 is played in 37 seconds, the identical span of time Gould needed to burn through it in 1955. But in the 1981 variations, Gould makes good on his desire for dignity. The 1955 rendition of No. 5 has a compelling, nervy energy; the 1981 version takes a greater sense of self-possession. The ability to find that much expressive room inside a similar tempo resulted in Gould’s second masterstroke with the Goldbergs.This range of musical investigation signals something profound. Two different approaches to the same notes can say a great deal about how one ages and how tastes can move over time.

Gould died just days after Columbia released the second Goldberg set. His death enhanced the idea of this being a grand, final statement—as though touching the work again had created a fateful resolution for his startling debut. But even if Gould were still with us, the 1981 Goldberg performance would sound necessary. Here, Gould luxuriates in the stately character of the “French” overture (No. 16)—and its pivot away from the prior, minor-key canon—with greater pomp than on his first try. It’s just that the fun never spills over into abandon, as on Gould’s first pass. For all his eccentricities, Gould’s most striking trait may have been his ability to revise his own carefully considered understanding of a work that was important to him.

Both interpretations have their uses. Along with Bob Dylan’s “Love and Theft”, which I’d purchased at 12:01 am on Sept. 11, 2001, at the Virgin Megastore in Union Square, Gould’s 1981 Goldberg set was the album I played most often in the days that followed. With the ashen smell still in the air, and the streets south of 14th Street devoid of car traffic, most who lived inside the perimeter established by the National Guard spent some portion of each day balancing requirements of mourning and anger with the search for a new equilibrium—a way to feel less anxious that didn’t also involve pretending that something traumatic hadn’t just taken place.

I owned both versions of Gould’s Goldbergs because I had been told by guidebooks that this was a prerequisite for caring about classical music (it is.) Until that week, I’d spent most of my time with the 1955 recording—identifying with its direct access to youthful exuberance. Now, however, the high energy of that edition seemed a poor fit to the mood. The dignity Gould had intended to emphasize in 1981 came through clearly.

Record collecting and music appreciation often turn on arguments about rankings, peerlessness, and the greatest-of-all-time. Classical fans play this game as aggressively as anyone—so hard that they occasionally seem to rule out the possibility of any worthy new music being made for traditional classical instruments. And we do this with Gould’s Goldbergs, too. Think fast: 1955 or 1981? Sometimes that’s fun. But these recordings’ mutual portrait of variations held in a single mind—one capable of such deliberate differences of opinion with itself—seems not just like something you’re well advised to have in a music collection, but instead like an approach to life worth exploring and emulating.