Die Frau Ohne Schatten, Roayl Opera House, London

A production best left in the dark

Any notions that "the woman without a shadow" might be overshadowed by David Hockney and his amazing technicoloured dreamscapes were quickly laid to rest when this pitifully inadequate staging was first unveiled in 1992. The designs were, and still are, the least of its problems. But they are the only visual information we have and as such classic instances of how a great painter's eye for colour and shape is often best left at the easel. Hockney's sketches and models look stunning in miniature but writ large on stage they are at best (the opening "spirit world rooftop") cutely exotic and at worst (the final tableau) a nightmare in garish orange on wrinkled canvas. That has to be the worst set ever to darken the Covent Garden stage. Except that – perversely – it's the one part of the production that is brightly lit. No wonder shadows are so sought after in the spirit world.

Not that there is any appreciable distinction here between the spirit world and earth. They do have one thing in common: bad acting in even worse cost- umes. The singers are shunted about like so many cut-outs in one of Hockney's models. Admittedly the human factor in this opera is somewhat subsumed by the metaphysical melodrama. But in lavishing so much on so very little Strauss and his librettist Hugo von Hofmannsthal at least threw down a gauntlet to the theatrically imaginative. The director John Cox leaves it to his designer to pick up, who promptly drops it.

But let's concern ourselves with matters musical, because that's effectively where the evening rallies. This is an opera for the heavyweights, and vocally and physically Covent Garden delivers. But if the key scenes between Barak, the dyer, and his wife don't really come off here, it's because Gabriele Schnaut wears everyone down with her stressed and shrewish and unremittingly unlovely sound. This is a voice to take cover from. Not one beautiful phrase, not even those that Strauss hands her on a plate in the opening scene of the final act. Mind you, when you consider that at the heart of the opera is the notion that women are only complete once they have bred, you too might feel aggrieved enough to scream the house down. Alan Titus's Barak is, by contrast, an oasis of calm and dignity seizing his opportunity in act three for some of his noblest phrasing; singing on the interest not the capital. A little something he might have passed on to his wife.

Meanwhile, in the spirit world, Johan Botha's Emperor sounds good and would sound even better if he would just free-up his phrasing a bit more. Jane Henschel's nurse, inhabiting that place where the sun don't shine amongst the tuba-heavy underworld of Strauss's miraculous orchestrations, really capitalises on the text's rasping melodramatics. From subterranean to stratospheric – at the opposite extreme of the vocal and tonal spectrum there is the Empress. Deborah Voigt is spectacular. Better, I think, than I have ever heard her, not just in terms of marrying the brilliant coloratura to those stupefying declamations and octave-plus plunges, but in the beauty and truth of her singing in the temple scene. She alone unlocks the humanity of the score.

That humanity, that love, largely eludes the conductor Christoph von Dohnanyi who it would seem has a constitutional resistance to the music's warm embrace. The Royal Opera Orchestra plays fabulously well for him, but as a reading it is all too one-sided – angular and hallucinogenic. Hockneyesque. With the shadow, but without the heart.

Further performances: 17, 20, 25 & 30 Oct (020-7304 4000)