Brazil's minister of song

Countercultural revolutionary to government official. Dusty outback accordionist to global pop star. Cultural provocateur to musical innovator. That's the extraordinary lifetime trek of Gilberto Gil.

An icon in his native Brazil, he's a renaissance man if ever there were one, a compelling performer and brilliant songwriter equally eloquent whether the subject is quantum physics or love. During the past decade, Gil's graying dreadlocks were just as likely to be seen cascading down the back of a well-tailored suit as a T-shirt, as he mingled in corridors of power as Brazil's crusading minister of culture.

Now on his first extended North American tour in a decade, Gil, 67, will play Orchestra Hall next Sunday in an all-acoustic "String Concert" featuring son Bem on guitar and percussion, and renowned composer/arranger Jaques Morelenbaum on cello.

The tour follows "Bandadois" (literally, "Band of Two"), a CD/DVD that he and Bem recorded live in São Paulo last fall. The spare arrangements spotlight Gil's subtly intoxicating, bossa nova-style finger-picked guitar and fine-grained voice, both imbued with the radiant spirit of his homeland. Sporting songs from throughout his 40-something-year career, it's a retrospective, but with a marvelously fresh feel.

In a recent interview via e-mail, Gil explained that the repertoire contains some of his biggest hits, but the main criterion was songs with prime roles for his acoustic guitar, "because acoustic is my original standpoint for composition and presentation of my music. It's basic. [The songs] have been rearranged, reconceived as musical pieces, and they sound quite different from their original versions."

"Bandadois" also has a neat symmetry -- juggling songs from the '60s to Gil's 2008 album "Banda Larga Cordel" ("Broadband"), spanning generations and paying tribute to inspirations. On one track, "Amor Até o Fim," Gil duets with singer Maria Rita, whose mother, the late beloved vocalist Elis Regina, recorded the song decades before.

"It is coincidental somehow," Gil said of the album's scope. "But it is also a result of aging. We start reflecting about the past, about things we've done before, about our personal history, history of our times, all of that."

Gil's history is particularly rich, and uniquely intertwined with that of Brazil and the international music community. A native of Salvador, Bahia, the northeastern state that is Brazil's most Afrocentric, he grew up with a wide range of influences encompassing bossa guitarist João Gilberto, accordionist Luiz Gonzaga and trumpeter Miles Davis.

In 1967 he, Caetano Veloso and a few others came up with a radical philosophy they called Tropicalia. It advocated a kind of cultural cannibalism, mingling diverse disciplines, but chiefly throwing together traditional Brazilian music and psychedelic rock 'n' roll. The spark was lit when Gil saw a link between the inventiveness of a traditional fife and drum band he heard and the Beatles' "Sgt. Pepper's."

The audacious sound and cultural turbulence fomented by Tropicalia inspired immediate controversy. Fearing youthful insurrection, Brazil's military government arrested thousands, including Gil and Veloso, who agreed to go into exile in England.

"The Tropicalia times were marked by a converging process of politics and behavior and values and art, science, everything," Gil said. "We were working with different levels of reality, of subjectivity, of fantasy all together. I was not surprised by the military government's reaction. Tropicalia was defying and provocative."

By the time he and Veloso were repatriated in 1972, the revolutionary tenor of the movement had faded. But Tropicalia's principles lingered, reemerging dramatically in the work of world-music samplers such as Paul Simon and Peter Gabriel and collagists like David Byrne and Beck. "It was a surprise that Tropicalia would become a reference, a classical movement for postmodern times," said Gil.

He stayed at the ministry longer than planned, but finally left in 2008 "because it was becoming too much of a sacrifice to do both jobs -- music and politics," he said.

Still, it was a remarkable turnaround, from political prisoner to government portfolio.