La rondine, Royal Opera House, London<br></br>Birmingham Contemporary Music Group. Festival Centre, Market Drayton<br></br>Rigoletto, Welsh National Opera, Cardiff

Puccini's an oxymoron, Bob's a wee bit difficult and Rigoletto knew Dean Martin

An unpopular Puccini opera. It sounds like an oxymoron, doesn't it? But La rondine – a romantic confection conceived and completed against the carnage of the First World War – defies convention. Its heroine's wistful, self-deceptive aria Che il bel sogno is all that most people know of this bittersweet score now, and that's largely down to its use in the soundtrack to A Room with a View. Product placement like that is not to be sniffed at, so why has La rondine taken 85 years and opera's most bankable couple – Angela Gheorghiu and Roberto Alagna – in the lead roles to finally achieve its Covent Garden debut?

History has left many snippy comments on La rondine's lack of musical development, its unevenness, its hybrid style and its half-seriousness. "Bad Léhar" was the verdict of one contemporary, while Puccini himself once grumpily described the libretto as "un solenne porcheria" – a complete pig-sty or pork chop, depending on your dictionary. Is it opera or operetta? A tribute to the 19th-century ideal of self-sacrifice? Or a wry examination of 20th-century self-interest? Certainly the doomed love-match between Magda (a dreamy traviata-manqué and the "little swallow" of the title) and Ruggero (a big-hearted bourgeois bumpkin) clashes badly with the pragmatic on/off liaison between Lisette (Magda's more modern-minded maid) and Prunier (a poet-come-lounge-lizard) that serves as a comic sub-plot. More worryingly, Magda's motive for abandoning Ruggero at the opera's lachrymose climax is unclear. Unclear, yes. But unsatisfactory? No. La rondine is sumptuous, delicate, daring in its pentatonic orientalism and rhythmic range, and, above all, sincere. If we have to play with taxonomy, La rondine is the proto-musical – a source for that winsome blend of the domestic and the exotic that Gershwin and Rodgers would go on to so cunningly exploit in their orchestration – and, as Nicolas Joël's opulent Art Nouveau production argues, if you want to understand its charm you must embrace its stylistic ambivalence. Failing that, you can simply sit back, drink in the spectacle – breathtaking stained glass, tiling to rival The Criterion, squealing dancers with fuchsia cami-knickers, glorious Vionnet-style dresses, even a mirror-ball – and listen to some truly glorious singing.

Whether Joël and Gheorghiu agree over Magda's motivation is debatable. (Though Joël's programme notes indicate our heroine's need to escape the strictures of small-town married life, Gheorghiu's performance indicates nothing less than total, tragic sacrifice.) But for an actress whose physical – and sometimes vocal – gestures can stray towards hamminess, this is a performance of touching simplicity that perfectly captures both Magda's idealism and her selfishness. The passage from note to note is as natural and unforced as a bird in flight, the tone exhilarating and extraordinarily sweet through what is a demanding, centre-stage role. Alagna, in what is very much the supporting role of Ruggero, provides a straightforward pleasing sound, a simple-hearted, sunny presence – Ruggero's halting desire to be a father is a particularly affecting moment – some toothsome top notes and one half of what must be the longest stage snog ever seen at Covent Garden. It's not a sophisticated performance, but it's not a sophisticated role. That element is provided by Charles Workman, whose debonair manner and smooth, intelligent singing make a likeable rogue of the slippery Prunier.

Our hero and heroine may have the big numbers (the chorus get their moment too, though Act II's opening is hampered by poor sight-lines) but the meat of human interaction – and the clearest evidence of Puccini's sympathy to foibles, tics and individual weaknesses – is in the multiple supporting roles. Workman is the best of the bunch. A millimetre behind him is Darren Jeffrey, in the small but pivotal role of Rambaldo (Magda's original lover), whose indifference to Magda's infidelity underlines the inevitability of the lovers' eventual separation. Magda's fluttering girlfriends (Mary Hegarty, Jacqueline Miura and Eirian James) coo luxuriously through their Act I trios – beautifully supported by the orchestra under Gianluigi Gelmetti's expressive beat – and only Cinzia Forte, miscast and over-broad as Lisette, is harsh of tone. A wonderful evening nonetheless and one that should provide a well-deserved and permanent nest for Puccini's little swallow.

So from the demi-monde of Paris to the demi-monde of Market Drayton ("The Home of Gingerbread") where Birmingham Contemporary Music Group brought spatial music to a small audience in an even smaller space. BCMG's Shropshire tours are a well established part of their work but as a first-timer I was nervous. The combination of beige carpeting, enforced intimacy, and the messianic gleam in artistic director Stephen Newbould's eyes as he started his introduction made me wonder whether I'd wandered into a branch of Atonalists Anonymous. Would we be called upon to share our feelings? To admit or invent an addiction to Berio? But the gleam became a twinkle as composer Gerald Barry shuffled up to chat self-deprecatingly about his new work, Bob. From the first electric, frenetic figures that BCMG's excellent clarinettists Alex Allen and Mark O'Brien played it was clear that we were all in this together, regardless of our preconceptions about "difficult" music. If the acoustic didn't flatter, if moving a flute five paces down the aisle failed to conjure the breadth and shimmer of Marc-André Dalbavie's Palimpseste, if Morton Feldman and Samuel Beckett's Words and Music was performed in unfortunate counterpoint to the church bells outside, the vitality and immediacy of this experience more than compensated. Model music-making, with all the polish and expertise of BCMG's larger-venue concerts.

Do you buy the Duke of Mantua as JFK and Rigoletto as Jerry Lewis? Can you see Gilda in pyjamas and bobby socks? Me neither, but Welsh National Opera's cheap and cheerful Washington-set production of Verdi's tragedy still has much to recommend it: Patrick Summers's brisk conducting, director James Macdonald's slow and subtle revelation of the Duke's true character, Celena Shafer's unselfish, athletic Gilda, and Joseph Calleja's Duke. At just 24 years old, Calleja has the kind of voice most 30 year old tenors would dream of – glossy, virile, lyrical and powerful. And guess what? He uses it beautifully. Catch him in a small house while you still can. This boy's going far.

a.picard@independent.co.uk

'La rondine', Royal Opera House, London WC2 (020 7304 4000), to 22 May. 'Rigoletto', Cardiff New Theatre, (029 2807 8889) to 23 May, then touring