Spanish Harlem Orchestra: Going back to their roots

There are still many roads for Latin music to explore. Of course, some of the most fascinating lead backwards, as sundry nouveau-riche old Cubans will attest. Now in its third year, London's La Linea Festival has swung most ways, from cutting-edge Cuban hip-hop and dub tango, to the grandfather of all Cubans, Compay Segundo. This year, La Linea's retro offering is restricted to one act, but an act of major class and stature: the Spanish Harlem Orchestra.

"The last great untold story in the history of American music," says the New York record producer Aaron Levinson, talking up his latest project, a new group resurrecting the overlooked heritage of Harlem's Latin musical population. Harlem was not only Duke Ellington at the Cotton Club and James Brown at the Apollo, runs the theory. Mario Bauza and Machito played there too, and dozens of Latin aces, from Chano Pozo to Mongo Santamaria, were integral to the scene.

The core musical forms the Latins brought to New York – son, mambo, descarga, cha cha cha – were Cuban, but the men who transformed them with jazz and a hard urban edge were primarily Puerto Rican, members of the great immigrant community of East Harlem, which became Spanish Harlem, or El Barrio.

Levinson's baby, the debut CD Un Gran Dia en el Barrio (A Great Day in the Barrio) by the Spanish Harlem Orchestra, is to be the district's "answer to the Buena Vista Social Club". In fact, the new band's brief turns out to be more restricted, but just as worthy. Rather than covering a broad spectrum of styles, the Spanish Harlem Orchestra's chosen repertoire is the Nuyorican's most distinctive contribution to the Latin musical world: the tough urban hybrid christened salsa in the early Seventies, and latterly salsa dura, hard salsa – in contrast to the light pop salsa romantica, which superseded it in the Eighties.

There are no Buena Vista pensioners in the orchestra, but top-flight session players led by the salsa era musical director Oscar Hernandez, who explains, "this is the music I grew up playing". As for Buena Vista-style musical heritage tourism, opportunities are limited. Most of the legendary clubs have gone – the Palladium is a fitness centre, the Corso a store.

Even Spanish Harlem itself has evolved, many of the Puerto Ricans having dispersed into the suburbs. But it hasn't changed that much. El Barrio announces itself via the street signs – Tito Puente Way, named after the great timbales drummer and bandleader, and Machito Square, after Frank "Machito" Grillo, Puente's predecessor as king of Latin New York.

Saturday night outside the subway exit on 96th Street, a Mercury people-carrier cruises by, horn beeping out the identifying signal we've arranged by telephone, the one, two, three – one-two key beat – the clave – central to salsa. My lift to the Spanish Harlem Orchestra gig. At the wheel is the burly goateed figure of bassist Ruben Rodriguez and behind the seats a red Ampeg Baby Bass, the Stradivarius of salsa basses.

This is one more gig in a busy schedule for Rodriguez. "I was playing last night with Johnny Pacheco and Papo Lucca [the top Puerto Rican keyboardist and arranger]. Wow, that was a hot one." We head for Ruben's next pick-up, the singer Frankie Vasquez, who keeps us waiting outside his Seventies tower block while Ruben phones amicably irate messages laced with terms such as pinga (dick).

Here, just below Spanish Harlem's main thoroughfare, 116th Street, the Barrio retains much of the look of early Fania Records sleeve art – rundown five-storey brownstones, with zigzagging iron fire escapes, razor-wire fences around vacant lots, the odd gaggle of bums. There's even a hydrant gushing water into the street.

Frankie saunters up to the car looking like a slightly louche attorney in dark overcoat, patent shoes and much cologne, ready for live action after a day in the studio with his own band, Los Soneros del Barrio.

This is only the eighth gig in the Spanish Harlem Orchestra's existence, but Frankie is feeling good about it. The band was nominated for a Grammy award and the debut album is lingering in the Billboard Latin Top 20 and heavily featured on the airwaves in Puerto Rico. "I think this band is going to do wonderful things, outside the Latin market," he says.

The gig is a smart charity supper dance in the Bronx. By the time the Spanish Harlem Orchestra strikes up on the small stage, the floor is already filled. Men in suits or tuxedos, women in flashy frocks and major hairdos; these are serious dancers accustomed to the accompaniment of a top-class old-school Nuyorican salsa band.

Ruben Rodriguez's measured sonorous bass supports a web of angular keyboard tumbaos from Oscar Hernandez; the back line stabs brass, Bobby Allende's bongos bubble under, ready to rip out a staccato filler burst. The lead singers alternate against the chanted coro and launch into their improvised soneo or inspiracion passages. Frankie Vasquez uses the middle section of "Somos Iguales" ("We're Equal") to compliment the dancers, half of whom he seems to know – now Willy's dancing down there with us, he sings, we're all equal, "Somos Iguales", holding up three fingers discreetly to the musicians to indicate the bars left before he finishes and Oscar Hernandez can take the band into the mambo section and crank things up yet further.

One am. Hernandez sits in the foyer during the band's break while the dancers queue at the bars. Given the excellence of New York's musician corps, could he have called on another 12 completely different musicians for the Spanish Harlem Orchestra? "I probably could, but not too many more than that," he says. "These are really the top freelance guys in New York now." Hernandez is close to the pinnacle of Latin musical direction, both in purist Latin music – Mongo Santamaria, Conjunto Libre, Ray Barretto – and the crossover market: the Mambo Kings movie soundtrack and Paul Simon's ill-fated but musically brilliant Capeman stage show. His team constitutes a microcosm of New York's salsa history.

Will it work internationally? There's every reason for optimism. Salsa dura has long had a fanatical base in the UK, then there are the ubiquitous salsa classes. Above all, if the millions of Buena Vista converts take the chronological step from 1950s Havana to 1970s New York, it could be a very gran dia indeed in the Barrio.

The Spanish Harlem Orchestra play La Linea Festival at The Royal Festival Hall, London SE1 (020-7960-4242) on 26 April