Click here to listen to the El Gusto Orchestra's Min Yaati Kalbou Lil Melah

Click here to listen to the El Gusto Orchestra's Lalla Fatima

Luc Cherki is a big man. Carrying his guitar, he approaches the microphone with the swagger of Johnny Cash and sings a folk ballad about the dispossessed worthy of the Man in Black that elicits whoops of recognition from his audience. But this is Marseilles, not San Quentin, and Cherki is French. His song, Je suis un pied-noir, tells of having to leave Algeria for France 45 years ago, thus becoming an emigré in his own country.

Accompanying him are the El Gusto Orchestra, veterans of Algerian music’s postwar golden age, when the sound of chaabi united the streets. When the war of independence (1954-62) tore apart the French colony it ripped the heart out of the musical community. For many of those onstage in Marseilles El Gusto is the first time they have seen each other in 45 years.

Now the old friends’ schedules includes a film, a tour by the orchestra, which reaches the Barbican in London on October 10 as part of its annual Ramadan Nights season, and an album, produced by Damon Albarn and released on his label, Honest Jons. “I didn’t know chaabi before I became involved,” Albarn admits. “But after I got the call asking me to contribute to this project I made sure I was well-versed before I got here. Then all I needed to do was to put microphones in the right places and try to capture the rawness of the music. I just told them they were the maestros and let them get on with it.”

El Gusto is the brainchild of Safinez Bousbia, a Dublin-based Algerian. “I was in Algiers in 2003 and saw a picture of musicians on the wall of a shop,” she explains. “The owner told me this was his class in the 1950s but that he still imagined himself playing the music again. At that moment I decided I had to put together an orchestra and make a documentary.”

Bousbia contacted a number of musicians who expressed interest in performing at a concert if she could pull it off. Albarn, fresh from playing the first dates by his band the Good, the Bad and the Queen, leapt at the chance of travelling to Algeria to do more.

Chaabi reflects Algiers’s status as a crossroads. In the ancient Casbah, black African and Berber rhythms mixed with Andalusian flamenco and Latin flash; the Jewish, European and North African residents brought their roots to the mix. “The Americans brought us many things during the war and afterwards,” explains the 79-year-old pianist Maurice El Medioni. “From them I heard jazz and blues. My right hand played Algerian music, my left hand played boogie-woogie, and I could integrate the two.”

He laughs: “Just like we played together, the Jews and the Muslims. It was natural.”

In the 1940s it was a scandalous sound, thriving behind closed doors. By the late 1950s, however, it had become the people’s music, played at weddings and religious festivals, and Mohammed El Anka, “the father of chaabi”, ran courses at the Algiers conservatoire. But the war of independence meant Europeans and Jews fled to Europe. It would have been difficult to replace such talents as El Medioni and Castel, but the Arabs who remained were forced to play only a classical repertoire. When the Casbah started to fall apart through neglect, the musicians were sent to live in outlying suburbs and music lessons ceased. Chaabi was dying a slow death and Algeria slid slowly into a civil war that would make it off-limits: musicians were seen as legitimate targets by hardline Islamists and murdered.

With the arrival of a shaky peace and wary visitors in 2002, there was a revival of interest in the old music. Bousbia’s determination to produce a concert in the Algiers Opera House has probably saved chaabi from dying out.

Now, in Marseilles, the touring orchestra is demonstrating how resilient it and its songs are. Introduced to the stage by a rabbi and an imam, who trade verses in song to wild applause and then leave the stage hand-in-hand, these are the former students of El Anka. Some stayed, others fled, all had lost their music but kept their dreams alive. When they reach the emigrants’ anthems Algeria, Algeriaand Ya Rayah, songs laden with untold layers of significance, the strength of emotion on stage and in the audience has to be witnessed to be believed. Memories flood back, old acquaintances are renewed; the musicians just don’t want to stop.

One such musician is Robert Castel. An acclaimed stage and film actor for nearly 50 years, he also left Algeria in 1962, after the end of the war of independence ushered in an Arab government. Castel, a Jew whose father, Lili Labassi, was one of the most revered writers of chaabi before the revolution, shakes with emotion as he sings the blues. He accompanies himself on the violin, perched upright on his lap in the Arab style, backed by a 40-strong orchestra of musicians who remember when their homeland had a thriving nightlife in which Jews, Muslims and Frenchmen played music together after dark.

Ahmed Bernaouio walks to the stage slowly, with the aid of a stick. He sits stiff and straight in his chair and has to have his lute handed to him. But when he starts playing, a deep primal blues of inspiring authority fills the auditorium, his voice as rough and compelling as Tom Waits’s. “Fifty years ago, I was among the first to play chaabi in the conservatoire,” he remembers, beaming. “Before that, this was the music of the streets, the brothels and the coffee shops. After the war it was banned, so to be playing it again after so many years is just beyond belief. It was the reason for my existence, and now I am here to keep it alive.”

But the proudest of all is probably Abdel Hadi Halo, the orchestra’s musical director and the son of El Anka. “I am keeping my father’s work alive, you must understand how important it is to me. This must have been what it was like in the Casbah 50 years ago. When we played in Algiers last year we were not able to bring over our Jewish friends, the circumstances were still not right, but now . . . soon . . .”

El Gusto play the Barbican, London EC2 (0207-638 8891), on Oct 10. The album, El Gusto, is released by Honest Jons on Oct 15

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