Andy Johns, the engineer and producer responsible for the Rolling Stones’ Exile on Main Street and Led Zeppelin’s Physical Graffiti has died.

Johns was hospitalized last week, but the exact cause of death is still unknown. Guitarist Stacy Blades, who was working with the producer at the time claimed that Johns had been suffering from liver problems, and this was the reason for his hospitalization.

The British-born producer racked up an enviable canon of experience over his storied career; apart from his multi-album tenure with the Stones and Zeppelin, Johns put his sonic signature on records for Jethro Tull, Mott the Hoople,  Joe Satriani, Television and Free among many others. His approach was a controversial and refreshing opposition to many other producers’, he claimed “I don’t build mixes…I start with everything… Most of the people that listen to and tweak one instrument at a time get crap. You’ve just got to go through it with the whole thing up because every sound affects every other sound.”.

This way of working gave Johns’ mixes a place in the heart of many musicians, and as soon as his death was announced the tributes quickly began to appear. Black Sabbath’s Glenn Hughes tweeted: “Larger than life-You are loved Andy.” and Red Hot Chili Peppers drummer Chad Smith noted that Johns “made some of my favorite all time records,”.

Johns is survived by two sons, Hurt drummer Evan Johns and singer-songwriter Will Johns. [via Billboard]