One evening in 1969, as the Beatles were working on a scorching new John Lennon rocker called "I Want You (She's So Heavy)" for their next album, an engineer popped his head into their London recording studio to deliver a warning.

"One of the guys says, 'There 've been some complaints from outside and we need to turn down a bit,'" producer Giles Martin said, recounting a favorite moment from the original session tapes he's immersed himself in while assembling the 50th-anniversary remix of "Abbey Road."

"The guitars were pretty loud, and there probably was some sound leakage. It's very late at night, and you hear John say, 'Is it OK if we do one more and then we'll turn down?'" Martin, 49, said between bites of a club sandwich on a recent visit to Capitol Studio B in Hollywood, unable to suppress a smile at the thought of anyone ordering the world's biggest rock band to pipe down. As Lennon tells his mates on the session tape, "Last chance to be loud!"

As with the two previous projects, Martin has gone back to the original analog eight-track master tapes, keeping contemporary ears and audio equipment in mind for this remix of the final album recorded by Lennon, Paul McCartney, George Harrison and Ringo Starr before they formally called it quits in 1970.

McCartney and Starr, whose bass and drum parts are generally the biggest beneficiaries of the remixes, have been enthusiastic about the updates. (Each Beatles reissue also is subject to the approval of Lennon's widow, Yoko Ono, and Harrison's widow, Olivia Harrison, before they are released.)

"For me, as the drummer, the remix is great because the drums – now you can hear them," Starr, 79, told The Times recently at Capitol Studio A in Hollywood. He noted how in the early days of the band's recording career, much of the bass content – most noticeably affecting the drums and bass guitar – was toned down to accommodate the record players in common usage at that time.

"In those days, if you wanted to take any of the bass off, you start with the bass drum stuff," Starr said. "If you listen to something like 'Love Me Do,' there's no bass drum, no bass, because we've taken that off."

The Re-Issue

The anniversary reissue will be packaged in several formats, the most ambitious being a box set comprising three CDs of audio tracks, plus a fourth Blu-ray disc with high-resolution versions of the album's new stereo mix, a 5.1 surround-sound version and another in Dolby Atmos audiophile audio, the first for a Beatles release. It will come with a 100-page book packed with session photos, introductions from McCartney and Giles Martin, a facsimile of one of George Martin's orchestral scores and new essays by Beatles historian Kevin Howlett and music journalist David Hepworth.

https://youtu.be/GQCfZ4uAAuE

"Everything we do is done with two things in mind," said Bruce Resnikoff, president and CEO of Universal Music Enterprises, which manages the Beatles' recordings in partnership with the group's Apple Corps Ltd. "One, we want to create something specifically for fans who've been there for as much as 50-plus years; we also want to create something engaging for young people who weren't around when the Beatles were first going."

The bonus audio discs with the "Abbey Road" reissue contain nearly two dozen alternate takes; studio chatter among the Beatles and other session participants; and demo versions of songs the foursome was working on at the time but were not part of the "Abbey Road" album.

Among them: both sides of their '69 hit single "The Ballad of John and Yoko" and "Old Brown Shoe"; McCartney's demo versions of two songs he handed off to other musicians he produced for their fledgling Apple Records label – Mary Hopkin's "Goodbye" and Badfinger's "Come and Get It"; plus an isolated track highlighting longtime Beatles producer-arranger George Martin's orchestral accompaniment for Harrison's ballad "Something."

As to Lennon's surprisingly polite response to the mid session request that he and the band back off, Giles Martin thinks it's a great example of one essential quality that suffuses "Abbey Road": that of a conscious victory lap for a group that had scaled virtually every peak the world had to offer.

"It's really sweet that you hear John say that," he said. "I think that everyone's on their best behavior to a certain extent.

"They know this is going to be their last album. You can tell they're going to make sure it's a good one and that everyone's songs are going to get equal attention."

Among the group's original studio albums, "Abbey Road" is their top seller worldwide, according to a UME spokesperson, and has been certified for sales of more than 12 million copies in the U.S. alone, according to the Recording Industry Assn. of America.

"Think about it," Giles Martin says. "The Beatles recorded some of their most successful, most popular songs on their last album. I can't think of another band that can say that." In fact, Harrison's "Here Comes the Sun" has become the most-streamed song in their catalog, according to SoundScan, even though it was never released as a single, while "Let It Be" is the catalog's most downloaded track.

Messing with history?

The "Sgt. Pepper" and White Album remixes were critical and commercial hits. Both received perfect 100 scores on the Metacritic.com aggregate website. The reissued "Sgt. Pepper" entered the Billboard 200 album chart at No.3 in 2017, and the more costly White Album reissue debuted at No.6 last year.

They also helped introduce the group's music to younger listeners. "The average age of the listener for Beatles music has actually dropped," said UME's Resnikoff. "Both 'Sgt. Pepper' and the White Album, in their initial streaming week, registered hundreds of more streaming than they had before. And they averaged a million more streams per week through the rest of the year than they had the previous year."