Back in 1967, Beatles producer George Martin spent three days mixing the stereo version of the band’s Sgt. Pepper’s Lonely Hearts Club Band album. But he spent three weeks mixing the mono version. That’s one of the reveals from NPR’s recent conversation with Giles Martin, son of the legendary soundman.

The younger Martin, who spearheaded the 50th anniversary Sgt. Pepper’s reissues project, also talked about bringing Ringo’s drums to life and about the weight of expectations for such an undertaking.

"You know, one of the criticisms of the stereo of Sgt. Pepper was that you couldn't hear Ringo,” he said. “Now we can have kick drum, because if you think about that time in 1967, there was a protection [system from producers and mastering engineers] with records then, so you didn't get the needle to jump out of the groove. We've done a great vinyl cut of this, which we did half-speed, so it's a much more precise cut. We still use the same techniques, we've just developed them."

Martin later added: “"You're challenged by this weight of expectation, but the joy is actually just finding how great Geoff Emerick's engineering was, how great my dad was as a producer, how organized the recordings are and, you know, the beauty the arrangements--and how great the Beatles were at playing."

To read more, or to listen to audio of the interview with Martin, click here.

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