The studio experimentation that had begun with Revolver advanced to the next level on Sgt. Pepper’s Lonely Hearts Club Band.

In many ways, 1966 had been a watershed for the Beatles. They had broken from the two-albums-per-year formula that had brought their record company, EMI, so much money, but which had occasionally depleted the group’s well of creativity.

Revolver was the only full-length record they’d released that year, and it had been an artistically satisfying album, made at a more leisurely pace and with greater creative latitude. Revolver was also the first time they’d worked with engineer Geoff Emerick, whose gift for creating sounds had helped them see new possibilities—and opportunities—in the recording process.

Importantly, too, it was the last album for which they would tour, putting an end to the relentless performance schedule that had occupied much of their time between albums. As 1966 came to a conclusion, the Beatles were officially a studio group, and with Sgt. Pepper’s they would indulge their new-found freedom in ways that made other artists begin to think of the recording studio as a creative tool in and of itself.

Emerick would play an essential role in this, as he had on Revolver. But ironically, the 21-year-old audio engineer had not a single new idea when the sessions began. Martin and the Beatles had agreed that they wouldn’t repeat techniques used in the past: no vocals through Leslie rotary cabinets, no “Tomorrow Never Knows”–style tape loops and no backward vocals or guitars.

“But unfortunately, I had used everything at my disposal on Revolver,” Emerick says. “On Pepper, it was like starting over from scratch, getting down to the individual tonalities of the instruments

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