Osvaldo Golijov has been called “the saviour of classical music” but the hyperbole does him no favours. Born in Argentina but living in New York since 1986, his music fuses many different traditions: classical, Jewish klezmer, flamenco, tango, whatever it takes to realise his vision.

If that makes him as much a collagist as a composer, that need not be a problem. Ainadamar (the title means “fountain of tears”), his first opera, unfolds in three acts, or “images”, as the composer calls them. That suggests a certain static quality, which this concert staging confirmed; action is thin, memory and emotion are paramount.

The plot, such as it is, focuses on the relationship between the Spanish poet Garcia Lorca and his muse, the actress Margarita Xirgu. Lorca becomes a Christ-like figure, martyred during the Spanish Civil War. David Henry Hwang’s Spanish text plays up the religious connotations but, at least in its surtitled English translation, is cumbersome.

Golijov writes well for the voice, in a rich, late-Romantic idiom. The principals, all amplified, knew their parts well; nobody needed a score, and generalised operatic acting helped tell the story. As Lorca, mezzo-soprano Kelley O’Connor achieved a mannish timbre that was both remarkable and moving, and there were stunning interjections from the flamenco singer Jesús Montoya, who, paradoxically, given Lorca’s love of flamenco, played the villain responsible for his death.

More from him would not have gone amiss but the star was Dawn Upshaw, an ethereal and tormented Margarita; Golijov clearly loves her voice, and she responds in kind. Under conductor Robert Spano, the City of Birmingham Symphony Orchestra seemed well inside Golijov’s multiple idioms, but over the 90-minute span, the evenness of his writing undermined the dramatic impetus. No saviour, then, but nonetheless an original voice.