Metallica's "... And Justice for All" was one of heavy metal's most influential albums, but fans who have listened to it countless times have long asked -- what happened to the bass?
Twenty-seven years later, the producer of the album has an answer -- the bass was turned down on purpose.
In an interview that has drawn interest and scathing commentary on heavy metal fan sites, producer Steve Thompson said that Danish-born drummer Lars Ulrich insisted that the bass volume go down to bring up the percussion.
"He said, 'I want you to bring down the bass where you can barely audibly hear it in the mix.' I said, 'You're kidding, right?'" Thompson said in a lengthy interview with UltimateGuitar.com.
Thompson said he threatened to quit but was stopped by his and Metallica's managers.
The producer said that Ulrich had apparently forgotten the episode when, years later at Metallica's Rock and Roll Hall of Fame induction, he asked Thompson why the bass was inaudible.
"I wanted to cold-cock him right there. It was a shame because I'm the one getting the shit for the lack of bass," Thompson said.
Thompson praised the playing of bassist Jason Newsted, who had joined the band after original bassist Cliff Burton died in a tour bus accident in Sweden.
Newsted in a 2013 interview called the inaudible bass "water under the bridge" and blamed his own inexperience in the studio.
"... And Justice for All" went on to become a surprise crossover hit despite its hard-charging thrash style and dark lyricism, making Metallica one of the few metal bands to earn both commercial success and mainstream praise.
Metallica has said it is working on a new album, its first since 2008's "Death Magnetic."