Los Angeles — Chuck Negron, a founding member of Three Dog Night whose lead vocals powered a string of hits including “Joy to the World,” “One” and “An Old Fashioned Love Song” for one of the top rock acts of the late 1960s and early ’70s, died Monday. He was 83.

He died of complications from heart failure and chronic obstructive pulmonary disease at his home in the Studio City neighborhood of Los Angeles, according to his publicist Zach Farnum.

Negron also sang lead on “Easy To Be Hard” and “The Show Must Go On.” The band’s other hits include “Black and White,” “Mama Told Me (Not to Come),” “Never Been to Spain” and “Shambala.”

In December 1972, the band hosted and performed on the inaugural edition of Dick Clark’s “New Year’s Rockin’ Eve.”

By 1975, album sales had declined and the band had its last Billboard Hot 100 hit with “Til the World Ends.” Internal strife fractured the group and it fell apart the next year.

In 1981, the group reunited, but Negron was dismissed in late 1985 because of recurring drug issues.

In 1967, Negron joined Danny Hutton and Cory Wells to form Three Dog Night, a vocal trio with roots in R&B, rock ‘n’ roll and urban doo wop. They found success two years later with their first million-selling single “One,” written by Harry Nilsson.

Negron engaged in heavy drug use during the band’s quick ascension to the top of the charts. He spent his fortune on drugs and even ended up on Los Angeles’ Skid Row for a time.

After numerous stints in rehab, he became sober in 1991 and went on to have a successful solo career, releasing seven albums between 1995 and 2017. His 1999 book, “Three Dog Nightmare,” detailed his ups and downs.

After decades of estrangement between him and Hutton, the two reconciled last year. Hutton and Michael Allsup are the lone surviving members.

Born Charles Negron II on June 8, 1942, he grew up in the Bronx singing in doo wop groups from an early age. His parents divorced when he was 2. He was recruited by California State University to play basketball, which brought him to Los Angeles, where he began working in the music industry.

In his later years, Negron toured despite having chronic COPD for three decades. The COVID-19 pandemic sidelined him permanently.

Negron is survived by wife Ami Albea Negron and five children, including Berry Oakley Jr., the son of Allman Brothers Band bassist Berry Oakley, who was killed in a 1972 motorcycle accident. Negron was for a time married to Julia Negron, the younger Oakley’s mother, and helped raise infant Berry Jr.