Rick Rubin has been called “the most important producer of the last 20 years” by MTV. Time Magazine listed him among the 100 Most Influential People of 2007. He has worked in such diverse areas a hip-hop, classic rock, heavy metal, and country. Yet his stripped-down approached to music production — one that focuses on artists and not artifice —is a signature sound that crosses all genres of music. And it makes him one of the most sought-after producers in the music business.

Johnny Cash. System of a Down. Jay-Z. Adele. The Dixie Chicks. Rarely would those acts be placed in the same article together, let alone worked with in a studio by a man who helped redefine each of their sounds. But that is quintessential Rick Rubin. Not defined by limitations of genre or confined to what’s popular on the charts, Rubin has spent the last thirty years getting the best out of artists by having them step outside of comfort zones, strip down to essentials, and open up with an honesty that few, if any other producers could obtain. In the process, he has, consciously or not, challenged the status quo.

“I don’t know anything about music,” he told Esquire Magazine in 2007. “My job has very little to do with music. It has more to do with taste and culture and balance.” A difficult combination to quantify taste, culture, and balance would seem to suggest that Rubin is part fan and part philosopher. He knows what he likes to hear, and senses what the rest of us want as well. His is not a music landscape of similar-sounding acts that define a genre, but an ideal where the most talented artists are able to sound their best in a studio where Rubin can bring out the best in them. His methods are often considered unconventional — especially when it comes to stripped-down instrumentation and full-presence with little effects of an artist’s vocal — but the results are unquestionable.

His career started with LL Cool J, the Beastie Boys, and Run DMC. Following the foundation of Def Jam records (from his NYU dorm room) in 1984, Rubin —with eventual help from Russel Simmons — tapped into a cultural revolution where rap had become the music of the streets, and a generation of kids, from New York City to suburban America, were hungry for it. These acts were outsiders, and Rubin found a way to raise their relevance by doing little more than giving them crisp instrumentation over which the impact of rapped lyrics could be clearly heard. But it didn’t begin and end with rap; Def Jam found other disenfranchised acts that had difficulty getting attention from other labels. Most notable was Slayer, a metal band that was a huge departure for the label, and the Cult  — whose 1987 Electric transformed them into a stripped-down, kick-ass rock ‘n roll band from which Rick cultivated songs like “Love Removal Machine.”

In 1988, Rubin quit Def Jam and headed to Los Angeles, where he founded Def American (which would eventually become American Recordings in 1993 — after Rubin rejected the then cultural implications of the word “Def”). Continuing his success with heavier rock bands, Rubin turned to Danzig. And that opened the way for more traditional rock bands like The Black Crowes, whose 1990 album gave American their first major success, and whose follow-up, 1992’s The Southern Harmony and Musical Companion, gave the label its first #1 album. There was hip-hop, too: Sir Mix-a-lot got a lot of attention for “Baby Got Back,” that same year.  He also gained notoriety for the meteoric rise of the Red Hot Chili Peppers, whose firth studio album, Blood Sugar Sex Magik (1991) — produced by Rubin — gave the band their first hit “Give it Away,” a song that won a Grammy Award in 1992 for “Best Hard Rock Performance With Vocal” and became the band’s first number one single on the Modern Rock chart. Rubin’s association with the Chili Peppers would go on to be one off the more successful of his career.

The other association with an artist — and the one for which Rubin may best be remembered — is his work with Johnny Cash. Cash, coming out of a lost period where his record company had dropped him and his relevance had seemed long past, was encouraged by Rubin to record many of his old songs (like “Delia’s Gone”) alongside covers of works by Tom Waits, Nick Lowe, Leonard Cohen — even Glen Danzig. These “American Recordings” would be released throughout the nineties and into the new millennium, outliving even Cash himself with two albums released after his death (American V: A hundred Highways and American VI: Ain’t No Grave).

It is with Cash’s cover of Nine Inch Nails’ “Hurt” (in 2002) that both the man in black and the man with the beard each may have found the most powerful and profound recording of their respective careers.

For Rubin, it is a career that took him well — successfully well — into the new millennium. And found him working with one of the most charismatic and popular artists of the last twenty-five years: Jay-Z. Their collaboration, The Black Album (2003) produced a song only second to “Hurt” in its mastery: “99 Problems.” Rick’s suggestion that “99 Problems” start a-cappella was a masterstroke.

Rubin’s methods may not always be met with instant positive reaction from artists; many struggle with his opinions. As Billboard reported, Adele had to re-record and reconsider elements of 25 because of Rubin’s advice. But she acquiesced, and all parties now seem happy about it. Arguably, it’s the push and pull he has had with many artists that have helped them produce their best work.

Over the course of thirty plus years, Rick Rubin has had his hand in one way shape or form in over 200 releases by radically diverse artists. Too many to document here, his production discography can be found (like most things!) on wikipedia. Most recently, he has helped Smashing Pumpkins dig deep to find their purest alternative rock roots on “Solara,” a song set to appear on one of their planned upcoming LPs.

Who will he turn to help transform next?  To paraphrase him, it would most likely be an act of taste, important to culture, and one in need of the balance that only Rick Rubin as producer can bring.