Credit: Jorge Herrera/WireImage

Everyone’s favorite Australian rock band (sorry, Tame Impala) has lost another of its founding members. On Wednesday, the band announced that rhythm guitarist Malcolm Young, the brother of the band’s lead guitarist Angus, had left the band due to health problems. The group still plans to release it sixteenth studio album, Rock or Bust, in December and to go on a world tour next year.

News of Malcolm’s health problems first surfaced in April, leading to speculation that the band would call it quits on their four-decade career. “It’s not just that he is unwell, it’s that it is quite serious,” Mark Gable, a friend of Malcolm’s, said at the time. “He definitely won’t be able to perform live. He will probably not be able to record.”

For now, it seems that AC/DC will remain intact, though that’s a fairly loose definition: Angus is now the only remaining member of the group’s original lineup. Stevie Young, Angus and Malcom’s 57-year-old nephew, will replace him. Bon Scott, the wild vocalist heard on early AC/DC hits like “T.N.T.” and “Highway to Hell,” died in 1980 from complications after a heavy night of drinking. Of course, the band weathered that loss by bringing aboard Brian Johnson and churning out a string of classics including “You Shook Me All Night Long,” “Hells Bells,” and “Back in Black.”

Though a less prominent part of AC/DC’s sound, Malcolm was still a crucial component. He surprisingly used medium-sized amplifiers set to moderate volumes, contradicting conventional rock wisdom that rhythm guitarists should turn up to 11. Like other famous rhythmic fiends—the Rolling Stones’ Keith Richards, and the Grateful Dead’s Bob Weir, Metallica’s James Hetfield—Malcolm often defined his band’s sound, despite his lack of axe acrobatics.

He may no longer be about to rock, but Malcolm Young—we salute you.