Ariadne auf Naxos, Royal Opera House, London<br></br> Berlin Philharmonic/Rattle, Philharmonie, Berlin<br></br>La clemenza di Tito, Royal Opera House, London

Harlequin as Becks? It's opera's new look

Take two conductors in their early middle age, appoint them as the hot new directors of two of Europe's most acclaimed musical institutions and watch what happens next. For the conductors it's a chance to change the aesthetics of a world famous organisation. For the organisations, a chance to tempt new audiences and benefactors with the buzz of fresh talent. But there the parity ends. For one there is a city-wide poster campaign and a first-night foyer thick with international news crews. For the other, a snippy paragraph in the editorial column of a local newspaper and a documentary on digital TV.

You'll have guessed by now that these conductors are Sir Simon Rattle and Antonio Pappano, whose inaugural performances with the Berlin Philharmonic and the Royal Opera House this week marked the ascent of the baby-boomers to the top of the musical heap. You may also have guessed which one got the red carpet treatment from his new home city. But for all the attention lavished on Rattle's first concert at the Philharmonie, it is Pappano's first new production at Covent Garden that represents the more radical change in direction.

An opera within an opera, Ariadne auf Naxos mercilessly lampoons operatic conventions only to plead eloquently in their defence. Taking as its subject this art-form's inherent absurdity and only occasional profundity, it's a difficult work to balance. It can seem lumpy, waspish and arch; at once over-written and incomplete. But in this sassy, tender, quick-witted, curvaceous and cohesive production, Ariadne is both an irresistible ensemble piece and a model for the new Covent Garden regime.

Though every aspect of this production bears the stamp of Antonio Pappano – from the reduced orchestral forces (as specified by Strauss but often ignored by conductors) to the young, clear-voiced cast and the bold coups de théâtre of debuting director Christof Loy and designer Herbert Murauer – Covent Garden's new Music Director seems happy to play accompanist in the pit. His reputation may have been built on the thick brocade of Italian and French repertoire but he understands Strauss's slippery idiosyncrasies; the boudoir colours of his instrumentation, the sudden shifts in scale, the different idioms of aria and lied. More importantly, Pappano understands singers. His orchestra moves deftly between tea-dance frippery, blowzy cabaret and lush melodrama; underlining, amplifying and illuminating the dialogue between the high art of the Composer (Sophie Koch) and Ariadne (Petra Lang) and the gum-snapping pop culture of Zerbinetta (Marlis Petersen).

On stage, Christof Loy has also found balance in Ariadne; suggesting backstage bustle without upstaging the foregrounded singers and gently clearing an intimate space for our suicidal heroine's climactic capitulation to happiness. Not a single gesture is wasted here. Petersen's vibrant physicality, comedic flair and gymnastic coloratura are so compelling that you barely notice the vertiginous pitch of Zerbinetta's lines, while Koch brings a rich, lippy, darkly direct tone to the Composer's earnest ambitions. Both are beautifully offset by the world-weary Music Master (Thomas Allen), the gleeful Major Domo (actor Christoph Quest) and the lascivious Dancing Master (John Graham Hall).

Of the other supporting roles, Alice Coote's Dryad stands out for gravity, Rachel Nicholls's Echo for simplicity, and Nathan Gunn's mohican-ed Becks-symbol Harlequin for erotic impact. Only Lang and Robert Brubaker (Bacchus) give any cause for concern: the one sounding a touch too opulent – a natural consequence of casting a mezzo in this role – the other slightly undernourished. But these are tiny niggles in a show I would recommend to anyone. Funny, sexy and moving too. Who'd have thought it?

That Berlin reacted to Rattle's first concert as Chefdirigent of the Berlin Philharmonic with an excitement close to hysteria was rather less surprising. This orchestra is undeniably fabulous: blistering in its attack, unbeatable in its dynamic and tonal control, and highly observant of its long-awaited conductor. Each section, from the brazen clarinets and athletic brass to the laser-bright first violins, is simply the best available. Likewise the extraordinary acoustic of the Philharmonie. Which might explain why Sir Simon had few qualms – give or take a euro or two – about moving to Germany. Especially after insulting the vast majority of young British artists last month.

During the first piece in the programme, Thomas Adès's tirelessly inventive Asyla, my thoughts were inevitably drawn to artist Dinos Chapman. More specifically, I found myself wondering what Chapman might make of the man he called a "boring twat" bringing a 25-minute long, techno-inspired orchestral work on the effects of Ecstasy to an audience that included half of the German government? Sensation indeed. But despite the pre-performance murmurs that Adès would prove unpopular at the Philharmonie, Asyla received as enthusiastic a reception as the Mahler and deservedly so. Berlin is far less conservative a city than it is made out to be and Rattle's programming and conducting style is, in truth, no more different to Abbado's than Abbado's was to Karajan's. Except when it comes to Mahler, that is.

Were it up to me, I'd choose Rattle's earthy, intellectual Mahler 5 over Abbado's more silken approach any day. But for some of the audience in Berlin, the ferocity and lack of sentimentality in his performance was obviously disquieting. Excepting a clean, hushed Adagietto, Rattle's account was pugnacious, unpredictable and questioning, displaying a good deal more yiddishkeit in its quirky woodwind colours than the Berliners may be used to in their treasured symphonic canon. Judging from the twiches in the balcony when the traditional points for portamento – an effect Rattle wisely rations – passed by without so much as tug, Rattle may have more difficulty converting Berlin to his core repertoire than he will in converting them to contemporary music.

And so back to Covent Garden for Dallas Opera's dire 1999 production of Mozart's most po-faced and propaganda-ridden opera, La clemenza di Tito. But where do I start? With Barbara Frittoli's silent screen voguing? With Vesselina Kasarova and Anna Netrebko's Iron Curtain Italian? With the bourgeoisification of the Roman Army? Or with Sir Colin Davis's inexorable, uninflected conducting? For the die-hard voice spotters, I'd suggest closing your eyes and listening to the wonderful Bruce Ford (Tito) and Katerina Karneus (Annio); both of whom at least understand how to communicate 18th-century recitative. For the rest of it, don't bother. In terms of Covent Garden's makeover, La clemenza di Tito is merely the "before" picture to Ariadne's "after".

a.picard@independent.co.uk

'Ariadne auf Naxos', Royal Opera House, London WC2 (020 7304 4000) to 26 Sept; 'La clemenza di Tito', ROH, to 21 Sept