Sgt Pepper's Lonely Hearts Club Band: 50th Anniversary

June 1, 2017 9:30 AM EDT

When the album Sgt. Pepper’s Lonely Hearts Club Band hit stores 50 years ago, on June 1, 1967, the record with the quirky cover photo represented a big change in tone for The Beatles — and, in doing so, captured the changing spirit of a radical time.

The group was “leading an evolution in which the best of current post-rock sounds are becoming something that pop music has never been before: an art form,” TIME wrote in a Sep. 22, 1967, cover story on the state of pop music.”‘Serious musicians’ are listening to them and marking their work as a historic departure in the progress of music — any music.”

Here’s the magazine’s description of how the album came together:

To achieve the weird effects on Sgt. Pepper, they spent as much as 20 hours on a song, often working through the night. The startling crescendo in A Day in the Life illustrates their bold, erratic, but strikingly successful method. Says Paul: “Once we’d written the main bit of the music, we thought, now look, there’s a little gap there; and we said oh, how about an orchestra? Yes, that’ll be nice. And if we do have an orchestra, are we going to write them a pseudoclassical thing, which has been done better by people who know how to make it sound like that — or are we going to do it like we write songs? Take a guess and use instinct. So we said, right, what we’ll do to save all the arranging, we’ll take the whole orchestra as one instrument. And we just wrote it down like a cooking recipe: 24 bars; on the ninth bar, the orchestra will take off, and it will go from its lowest note to its highest note.”

The 41-piece orchestra, as it turned out, consisted mostly of members of the New Philharmonia, who had trouble following the recipe. Unaccustomed to ad-libbing, they had to be cajoled by John and Paul, who threaded among the musicians, urging them to play at different tempos and to please try not to stay together. Partly as a result of filling that “gap,” the Sgt. Pepper album cost three months of work and $56,000 — which is about as much as it costs to record five albums for London’s New Philharmonia Orchestra.

All that work paid off artistically. Composer Ned Rorem told TIME that it made The Beatles “colleagues” of his, “speaking the same language with different accents,” and conductor Leonard Bernstein compared it to the classical work of Robert Schumann.

It also paid off literally: according to TIME’s original report, the album sold 2.5 million copies in its first three months.

How The Beatles Made Sgt. Pepper’s Lonely Hearts Club Band Work

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