Lopez, a founding member of the band brought together in the 1990s by American guitarist and producer Ry Cooder, died in a Havana hospital several days after surgery, said Manuel Galban, a Cuban musician who played with Lopez for decades.

“We have lost a great companion,” said Galban.

Born in Havana in 1933, Lopez became an international sensation as part of the Buena Vista Social Club – a group of elderly, sometimes retired, musicians who were living quietly in Cuba before Cooder brought them together and they became worldwide sensations.

“I will remember him as marvelous, both in his music and as a person,” Galban, a guitarist, said by telephone. “He was extraordinary, affable, a great bassist.”

Lopez died less than a week after turned 76.

“I called him last week because it was his birthday and his voice didn’t sound too good,” said musician Amadito Valdes, who added that Lopez had undergone prostate surgery several days ago. “He was a person who was always sharing with everyone around him, very noble.”

Lopez was held by many to be Buena Vista’s heartbeat and had played to international audiences as part of its touring company.

The group, which plays a mix of traditional Cuban rhythms, has lost many of its key members of late. Singer Compay Segundo – who was born Maximo Francisco Repilado Munoz – pianist Ruben Gonzalez, and vocalists Ibrahim Ferrer and Pio Leyva have all died in recent years.

But Lopez was also a star in his own right, independent of Buena Vista. His groundbreaking debut album Cachaito won a BBC Radio 3 Award for Word Music in 2002.

Lopez hailed from a family of at least 30 bass players, including his uncle, legendary bassist Israel “Cachao” Lopez. His nickname translates to “Little Cachao.” His father Orestes played piano and cello in addition to the bass and was also a composer.

Lopez originally played the violin, but as he said publicly many times, eventually switched to the bass after his grandfather urged him to take up the family craft.

He was a pioneer of Cuban mambo, and by 17 was part of a noted big band group known as Riverside. He later joined Cuba’s national symphony. He also played with a band called “Los Zafiros.”

Lopez was at home playing classic as well as popular music but also dabbled in late night jazz and jazz fusion.

However, he only gained international notoriety when Cooder brought him together with such standouts as Compay Segundo, Ibrahim Ferrer, Ruben Gonzalez and Omara Portuondo to form Buena Vista.

Later, Wim Wenders released a documentary titled Buena Vista Social Club, in which he profiled the musicians whose talents had all but been forgotten.

Family members planned to cremate the body but there was no immediate word on funeral services.