OPERA / Just a drop of Spain: Roberto Gerhard's The Duenna is receiving its British premiere next week. About time too, says Bayan Northcott

Next Thursday, at 7.15pm precisely, under the motley umbrella of the European Arts Festival, the Grand Theatre, Leeds, will resound to a major act of reparation. Roberto Gerhard completed his sumptuous setting of Sheridan's comic libretto, The Duenna, in 1947. The score was broadcast by the BBC in 1949, given a concert performance at Wiesbaden in the 1951 Festival of the International Society for Contemporary Music, and a second BBC studio recording in 1971, each time garnering fresh enthusiasm. Yet the upcoming Opera North staging will be the first in Britain - as, indeed, last January's Madrid production was the first ever. No doubt the precedence of Spain in reclaiming her own son could be deemed fitting enough, especially as his music had been virtually banned during the long Franco years. But just how Spanish was Roberto Gerhard?

He was certainly born in Spain, at Valls, outside Barcelona, on 25 September 1896. But his father was of German- Swiss descent and his mother of French stock from Alsace. His musical training was equally mixed. Between 1915 and 1922 he sat at the feet of the venerable Felipe Pedrell - scholar, folklorist and, in effect, father of modern Spanish music through his pupils, Albeniz, Granados and Falla. But instead of proceeding to Paris for the finishing touch, like them, Gerhard chose to complete his studies between 1923 and 1928 with Schoenberg in Vienna and Berlin, soon after marrying an Austrian wife. And when the triumph of Franco finally drove him from Catalonia in 1939, Gerhard found refuge not, like so many European talents of his day, in America, but in Cambridge, where he was to live until his death on 5 January 1970 - already regarding himself as an English composer long before he took British citizenship in 1960.

His professional career was almost as complex as his cultural background. During the 1930s, after his return to Barcelona, he was able to subsidise his composing by work as a librarian and editor of old Spanish music, as a journalist and musical adviser to both the Catalan and Central Republican governments. In England, despite - or more likely, because of - his Continental reputation and Schoenbergian connections, he was ignored for years by a reactionary musical establishment and compelled to support himself on a wearisome succession of functional commissions: wartime ballet scores for the Rambert and Kurt Joos, incidental music for the Shakespeare Memorial Theatre, BBC Third Programme features, technical articles for music journals, and so on. Not till the age of 60, when he was already stricken by the heart condition that would ultimately kill him, did he find an English publisher. Not till the accession of his long-term supporter, William Glock, to the BBC in 1959, was his real stature widely recognised.

Had Gerhard's compositional interests remained narrowly based - upon a handful of Spanish idioms, say, such as Falla worked so intensively, or a strict 12- tone methodology after the example of Webern - he could no doubt have gone on accumulating a hermetic output in detachment from the disruptions of his life. In reality, he seems to have been a personality of immense breadth and verve, formidable in the defence of his own music - as Lindsay Anderson discovered when he cut Gerhard's film score for This Sporting Life - but endlessly open to whatever musical stimuli presented themselves. Since these ranged from the vernacular, classical and modern traditions of Spain by way of Ravel, Bartok and Stravinsky to the Schoenberg school and, after the war, from the avant-garderie of Darmstadt to the latest electronic developments - not forgetting the Oriental music to which he was introduced by the Cambridge scholar, Lawrence Picken - the danger to his development would seem to have been an amorphous eclecticism.

Yet that ancient unity of Spanish culture by which the sacred and profane, the aristocratic and plebeian, the sensuous and aesthetic always seem to have been more profoundly interfused than anywhere else in Europe arguably guided Gerhard's evolution more than any specific details of musical language - that, and his own quite specific lucidity of ear. Just as the piano writing in the very early Seven Haiku (1922) already displays his acute sensitivity to the placing of notes and the resonant spaces between them, so the ostensibly contrasting pair of pieces he completed in 1928 on graduation from Schoenberg's master class - the grittily serial Wind Quintet and the picturesque Six Catalan Folk Songs - already lean towards the stylistic synthesis of his maturity. Or, syntheses - for, rather remarkably, Gerhard was to explore successively two quite opposite approaches to unifying his super- abundant material.

From the early 1930s to the beginning of the 1950s, he seemed positively to delight in testing just how many disparate stylistic elements could be held together within single works. Yet the output of this period yielded at least three major achievements: The Duenna itself, the much-revised one-act ballet Don Quixote (1940-50) so warmly received at this year's Proms, and the exquisite Violin Concerto (1943). Within the ample three-movement form of the latter, sultry folkloristic dance measures, Bartokian insect noises, chorales on the tone row of Schoenberg's Fourth Quartet, even oblique wartime allusions to the Marseillaise and air-raid sirens, are somehow conjured into the semblance of a unity in the darkly-bright ambience of Gerhard's musical sensibility. The result is one of the great mid-century concertos.

It was with the spectacularly self-generating surge of the First Symphony, completed in 1953, that Gerhard seemed to throw his approach to synthesis into reverse. From now on, his concern was more and more to abstract the gestural and coloristic qualities behind the styles he had hitherto juxtaposed, and to combine them in a new continuum. By the time of the Third Symphony (1960) - one of the earliest British works to combine orchestral and taped sounds - and the sensational Concerto for Orchestra (1965), Gerhard had arrived at a kind of supersonic play of sonorous frissons and great shimmering spaces - though, touchingly, the occasional Spanish echo still lingered to the last in the Fourth Symphony of 1968.

At the time of his death, these sweepingly unified late scores were widely considered the worthy climax of a career to which the more stylistically mixed middle-period pieces seemed merely a stepping stone. And, less dense than Carter, more coherent than Xenakis - to cite a comparable couple of masters of the hyper-modern montage - they retain their power to excite non-specialist listeners. Yet it is also possible to feel their streamlining was achieved at too great a sacrifice of musical substance, and that it is now the composite textures of the 1940s that seem to glow ever more richly - never more so than in The Duenna. Indeed, if this endlessly inventive fusion of neo-classical formality, Bergian passion and lilting Spanishry has a fault, it could be that the music is too rich for its apparently slight buffa plot of disguises and elopements in 18th-century Seville. But then, Die Meistersinger and Der Rosenkavalier were long criticised for the same thing until it was realised how subtly their scores explored beneath the surface.

Whether or not the dryish acoustic of the Grand Theatre will help the complex balances of The Duenna, it would sound wonderful in the Coliseum. May we hope that English National Opera will at last make good its unaccountable failure over the decades to bring forth Roberto Gerhard's masterpiece?

17, 19, 25 September, 7.15pm, Grand Theatre, Leeds (0532 459351)