An accordion-playing Frenchman? It's the ultimate musical cliché, and for many of us it comes complete with matching visuals: berets, baguettes and plastic models of the Eiffel Tower. Richard Galliano seems to fit all the clichés - until you hear his music, writes Arminta Wallace.

Richard Galliano is to those images what Billy Connolly is to tartan and shortbread. And when you put his cheeky deconstructionist accordion antics, known in France as new musette, together with the music of Astor Piazzolla, the Argentinian composer who invented nuevo tango, you get Piazzolla Forever, a joyous and jaw-droppingly accomplished album that is a lot easier to listen to than to describe.

One minute it's wheezy, squeezy Paris music hall, the next it's something akin to Stravinsky and the pounding asymmetric rhythms of The Rite Of Spring. The sultry tango backdrop is constantly undercut by sparkling jazz piano, snatches of Debussy tunes and - did I hear correctly? - a tart send-up of Pachelbel's Canon.

On the phone from his home, in Paris, Galliano chuckles gently. "Ah, bah oui," he says, for we are conducting the interview in French - or at least he is. At this end I am wrestling with some ridiculous pidgin language that is not so much franglais as stranglais.

Galliano is patient, relaxed, enthusiastic. "Astor studied music so that he could always retain his tango roots while mixing them with lots of other musical styles," he says. "So of course there is the influence of Bartók and Stravinsky. For my own part it was he who gave me the idea of mixing in the same way: of keeping my French musical roots while staying open to the influences of both jazz and classical music, which I love."

Why did Galliano, a well-established composer in his own right, choose to record an album of Piazzolla? "Well," he explains, "it's a homage to Astor, really. He was my friend. Ten years after his death I wanted to do something to pay tribute to him, so I took my favourite pieces of his and rearranged them for this particular combination of instruments. I didn't change the arrangements or the structure of the pieces, and I didn't change a note, I just adapted the instrumentation."

The instrumental combination in question is a septet composed of - well, of virtuosi on their respective instruments: two violins, viola, cello, contrabass and piano, as well as Galliano on accordion and bandoneon. Together they make up the ensemble that gave its name, Piazzolla Toujours, to the album. But while you need virtuosity to play this kind of music with the correct degree of panache, there's another ingredient in the mix which is, says Galliano, still more important. "In every kind of music, and especially in classical concert music, you have to achieve a certain technical level in order to express all the nuances of the music," he says. "But in this music you must also be sensitive to the style. The violins, for example - they must play in a way that is very close to what we would call, perhaps, gypsy music.

"It's often said that tango is sad music, but Astor's music isn't exactly sad; it's music which plays on feelings of love, passion and, above all, of life. There are some sad moments but also some passionate ones." He pauses, then concludes: "La vie, quoi. Voilà . . ."

To a man, Galliano's septet are classically trained musicians. "They are soloists who make their living with orchestras or playing chamber music, except for the pianist, who comes from more of a double-culture background. He's a jazz teacher at the Paris conservatory, and he also plays with people like Johnny Griffin. I made this choice deliberately in order to do a little smashing, shall we say, of expectations, of habits. Because he is not a tangiste, he brings a very original perspective to tango music. But all of the septet are mad about this music, so they give the best of themselves. Which, I think, produces quite original results."

Quite original? On Piazzolla Forever classical techniques and the tightly knit musical discipline of chamber ensembles combine with free-flowing jazz creativity to produce something very special.

But one of the most astonishing pieces on the album is also one of the simplest, a six-minute-plus solo by Galliano on the bandoneon, a kind of cousin to the accordion. "Ah, yes. I play this piece in a different way at every concert," he says.

"The version on the recording is one of a multitude of versions, one which has, more or less, succeeded. It makes a big impact on the audience because it's really a very beautiful composition. And it's the only piece of Piazzolla's which I treat as a jazz theme and improvise on." If Galliano produces yet another version of this one-man-orchestra spectacular when he and his septet play at Liberty Hall, on Sunday, the audience is in for quite a treat.

Galliano first studied accordion with his father, an Italian immigrant from Piedmont who moved first to Nice, then to Cannes, where Richard was born in 1950. In his mid-teens he won the accordion world cup twice in a row with performances of Bach, Gershwin and Tchaikovsky; he also studied trombone, harmony and counterpoint at the academy of music in Nice.

Around this time he began to take an interest in jazz, especially the work of the trumpeter Clifford Brown. In the early 1970s he joined the Claude Nougaro big band, where he spent a hectic and formative three years working as conductor, arranger and composer - and hanging out with the superstars of French chanson: Charles Aznavour, Juliette Gréco, Georges Moustaki and Zizi Jeanmaire. But it was Galliano's meeting with Piazzolla that finally synchronised this mass of influences into a coherent musical whole.

In 1983 the Argentinian composer invited him to be the bandoneon soloist at the Comédie-Française in his original music to accompany A Midsummer Night's Dream - and a firm friendship was born. "He was a person who loved life, who was very warm, who loved to go to restaurants, to eat and drink well. He was, as we say in French, a bon vivant. And besides this he absolutely adored music. He valued music above everything. It was, for him, like a religion."

Piazzolla encouraged Galliano to infuse the American jazz he so admired - and the classical concert tradition in which he was so thoroughly steeped - with a strongly Gallic flavour. Initially, Galliano regarded Piazzolla's advice that he should revisit his French roots with a sort of fascinated horror. It meant re-examining musette, the turn-of-the-century Parisian working-class dance music that, as far as jazz buffs were concerned, was anything but cool. "This genre of music was backward looking, outdated," he says. "It was as if you were to play the accordion in the style of the 1930s, as if Charlie Parker, John Coltrane and Jimi Hendrix never existed."

Piazzolla was right, of course: musette was part of Galliano's musical heritage. So, unable to ignore it, he radically reinvented it, much as Piazzolla himself had done with the tango tradition, adding jazz harmonies, improvisation and new instruments, such as the electric guitar. Hence Galliano's affectionate tribute to his musical mentor.

Just one of the tracks on Piazzolla Forever was not written by Piazzolla: Galliano's bittersweet miniature Laure Et Astor. Is there a story behind it? "Ah, yes, there is," he says. "I let Astor hear it six months or so before he died. And he said to me, it's very beautiful but also full of sadness. At the time there was no reason why I should have written a piece full of sadness about Astor and his wife. They often came to Paris, and, together with my wife, Giselle, we'd have great big meals, at home or in a restaurant.

"Perhaps it was a premonition on my part; perhaps I felt I was going to lose a friend. Because sometimes, in the middle of those moments of happiness, we realise that nothing lasts forever. But that's part of life too." There's just one possible reply to that. Ah, bah oui . . .

Richard Galliano and Piazzolla Toujours play Liberty Hall, Dublin, on Sunday; Piazzolla Forever is on Dreyfus Jazz