Bon Scott died on February 19, 1980. Back In Black was released on July 25 of that year, with new vocalist Brian Johnson, formerly of the UK glam rock band Geordie, up front. Scott was actually a fan of Johnson’s, and had praised him to Angus Young, so while he wasn’t their first choice — they auditioned two or three other candidates before calling him — he did come recommended. And indeed, with Johnson, the band has achieved truly monumental commercial success. Back In Black has sold over 22 million copies in the US, over 50 million worldwide.

The differences between Bon Scott-era AC/DC and Brian Johnson-era AC/DC aren’t vast, but they’re obvious. First of all, their vocal styles are completely different. Scott was a subtle, multifaceted performer capable of slyly winking at the listener, or conveying creepy menace, or leaning in for a boozy attempt at seduction. Johnson is a pliers-to-the-nuts screamer, harsh and hoarse, very similar in sound to Dan McCafferty of Scottish hard rockers Nazareth.

Secondly, AC/DC are slower, and less of a straightforward boogie band, with Johnson singing, particularly on their singles. This was actually more due to the influence of producer “Mutt” Lange, who worked on their final Scott-era album, Highway To Hell. The title track was the one of the slowest non-ballad songs the band had ever released; indeed, Lange slowed it down himself in order to give it greater impact. As producer on Back In Black and its 1981 follow-up, For Those About To Rock We Salute You, he likely had more impact on their sound — for good and ill — than anyone since Harry Vanda and George Young.

For a transitional album recorded in what now must seem like an astonishingly short time (the band spent April and early May recording in Compass Point Studios in the Bahamas, under tropical storm conditions that inspired the lyrics to “Hells Bells,” then moved to New York’s Electric Lady to mix), Back In Black is an incredible achievement. Not only are many of the songs qualitatively different from anything they’d done before, but it sounds a million miles beyond any previous AC/DC album.

Let’s talk about the drums. They sound amazing. They don’t sound like any drum kit I’ve ever heard in my life, but neither do they sound like a machine, or a giant steel door slamming, like they would had, say, Hugh Padgham produced the album. Lange gives them a kind of hyperreal quality, just reverbed enough to fill the entire middle of the mix, with the guitars positioned on either side and the bass somewhere underneath. Every instrument here gets similarly plush treatment; Back In Black is basically the Platonic ideal of a hard rock album, sonically speaking.

The songs are better, too. Sure, there are routine boogie tracks (“Shoot To Thrill,” “What Do You Do For Money Honey,” “Shake A Leg”), and songs that have a good chorus and little more (“Given The Dog A Bone,” “Let Me Put My Love Into You”), but “Back In Black” and “You Shook Me All Night Long” are absolute high-water marks for the Young brothers as songwriters — and Brian Johnson as a lyricist. Both tracks are packed with surprisingly witty lines and clever wordplay, but it’s their structure that makes them the classics they’ve become. That stuttering, funk-metal riff to “Back In Black” is totally unlike anything AC/DC had recorded to that point, and “You Shook Me All Night Long” has one of the biggest, catchiest choruses they’ve ever recorded and a brilliant main riff. Whether the Young brothers came up with this stuff on their own or were pushed in this direction by Lange, they absolutely graduated to the big leagues with these two songs.

Is Back In Black a perfect album? No; Side One should have been Side Two, and vice versa, and “Rock And Roll Ain’t Noise Pollution” is the definition of filler. But its peaks are fucking incredible, and as a comeback from a potentially band-destroying tragedy, it’s amazing.