Phil Spector, the disgraced producer who pioneered the “Wall of Sound” and worked with artists including the Ronettes, the Crystals, the Beatles, Leonard Cohen, the Ramones and the Righteous Brothers, has died at the age of 81.

Spector was convicted of murdering actress Lana Clarkson in 2009 and was serving a 19 years to life sentence at the time of his death. According to the California Department of Corrections and Rehabilitation, he passed away of natural causes in an outside hospital at 6:35 pm PST on Jan. 16, 2021. TMZ had reported Spector died of COVID-19 complications.

Born in New York City on Dec. 26, 1939, Harvey Philip Spector was one of music’s first well-known producers. Spector began his career in 1958 with the Teddy Bears and wrote their chart-topping single “To Know Him Is to Love Him.” The first song he produced was “Corinna, Corinna” by Ray Peterson in 1960, which also became his first top 10 hit.

At the age of 22, Spector co-founded Philles Records and became famous for his “Wall of Sound” production method. He described the process as a “Wagnerian approach to rock ‘n’ roll.” It was a dense, layered orchestral approach to instrumentation where multiple instruments play the same note together to create a fuller sound. The technique would later influence artists like Brian Wilson and Bruce Springsteen.

He went on to produce some of the most popular songs of the era with the “Wall of Sound,” including “Da Doo Ron Ron” and “Be My Baby” by the Ronettes, The Righteous Brothers’ “You Lost that Lovin’ Feeling” and “Unchained Melody,” and Ike and Tina Turner’s “River Deep, Mountain High,” before he took a short break. A few years later, Spector produced the Beatles’ Let It Be, followed by John Lennon’s Plastic Ono Band and George Harrison’s All Things Must Pass after the band broke up.

However, as Spector’s fame grew, so did his erratic and violent behavior. The producer’s ex-wife, Ronnie Spector of the Ronettes, said that he tortured her, keeping her in his mansion and threatening to murder her. She eventually escaped the home in 1972.

Spector was also known for carrying a gun into the studio. Ramones bassist Dee Dee Ramone said in his autobiography that the producer pulled a gun during the End of the Century sessions, though Marky Ramone would later deny that it happened. He was accused of doing the same thing to Leonard Cohen in 1977 during the recording of Death of a Ladies Man and reportedly to Lennon as well.

But his fame eclipsed his transgressions, and Spector was inducted into the Rock and Roll Hall of Fame in 1989.

On Feb. 3, 2003, Clarkson was found dead at Spector’s home in Altadena, California, suffering a gunshot wound to the head. After a mistrial in 2007, Spector was convicted of murder on April 13, 2009. Since then, he had been in the California state prison system.