Les Arts Florissants/La Descente d'Orphée, Barbican Hall, London<br></br>Cage Uncaged, Barbican Centre, London

Two to write home about

After 25 years of directing Les Arts Florissants, harpsichordist and conductor William Christie must surely count as one of the most influential musicians of his age. In a period when historically informed performance practice was still the province of kaftan-wearing academics, Christie brought glamour to Early Music; restoring all-but-forgotten French composers to international fame, launching the careers of a generation of younger artists, and making Baroque opera chic. Without Christie, few music lovers would have heard Montéclair's Jephté, Rameau's Hippolyte et Aricie or Charpentier's Médée, much less seen them fully staged. For Monteverdi, Purcell and Handel operas too, it is to France that we look. More than any of his contemporaries, Christie has been an educator as much as a performer and tastemaker: not just of his audiences, not simply through his decades of teaching at the Paris Conservatoire, but by example. A quick glance at the biographies of Marc Minkowski, Christophe Rousset and Emmanuelle Haim will confirm this. For aspiring conductors of Baroque opera, playing continuo under Christie is an education par excellence.

Like Gucci or Conran, Les Arts Florissants is a designer-label. Which explains why a semi-staged double-bill of obscure chamber operas by Charpentier - the 300th anniversary of whose death, along with the 25th and 60th birthdays of Les Arts Flo and William Christie, we celebrate this year - can ensure a packed house at the Barbican. A pity then that for half of this beautifully presented programme the material was so thin. As sentimental gestures go, performing the opera from which the group drew their name has a tinge of self-indulgence. Ravishingly scored but devoid of plot, Charpentier's idylle en musique is little more than a decorous - and futile, as it turned out - compliment to Louis XIV. Poetry (Sunhae Im), Music (Olga Pitarch), Architecture (Katálin Karolyi) and Painting (Cyril Auvity) celebrate peace and prosperity under the Sun-King, Discord (Nicolas Rivenq) rudely interrupts, Peace (Sophie Daneman) gently intervenes and with one pre-echo of the Fiat Misericordiae trio from Charpentier's later Te Deum, the Arts flourish again. Huh. Small wonder that this half-hearted allegory failed to break Lully's stranglehold on Versailles. But the perfunctory prelapsarian harmonies of Les Arts Florissants only underline the impact of La Descente d'Orphée aux Enfers.

Concise, psychologically acute and disturbingly delicious in its subtle underscoring of desolation, Charpentier's treatment of the Orpheus myth packs as many punches in one hour as Gluck and Monteverdi manage in three. No happy endings here. No endings at all, in fact, for as the opera closes Orphée and Euridice have yet to leave Hades. But ambiguity is Charpentier's greatest suit as a composer, as evinced by Médée's devastating climax. With exquisite playing from the two viola da gamba soloists Sylvie Moquet and Ariane Maurette, a blistering soundscape of oboe, bassoon and regal for Hades, Vincent Brossard's elegant, minimalist semi-staging, the sweetest rendition of the Carissimi-like chorus Juste sujet de pleurs, and the most committed central performances from Paul Agnew (Orphée), Daneman (Euridice) and Rivenq (Apollon), this was a performance to be celebrated. Happy Birthday, Mr Christie. And may there be many happy returns.

Could I say the same of Cage Uncaged? Not all of it, no. But what fun to see The Sun print a feature about a BBC Symphony Orchestra composer weekend! Given this sudden surge of popular interest in John Cage, I feel newly optimistic about the classical music industry and am eagerly anticipating The News of the World's in-depth analysis of Thomas Adès's new opera. Assuming The Tempest is silent and has a duration of four minutes and 33 seconds, that is.

I know. It's easy to poke fun. But were it not for one theatrical cough from a disaffected anti-modernist - the bronchial equivalent of "Hello Mum!" - and the daft juxtaposition with Copland's twinky El Salon Mexico and Antheil's utterly irrelevant Jazz Symphony, the much-mocked orchestral version of 4'33'' might well have been one of the most interesting moments in my concert-going career. If only it had been programmed for the second of the BBCSO's evening concerts: Cage and his Heroes. If only we'd heard it after Varèse's Amériques or Ruggles's Sun-Treader - both performed magnificently by the orchestra under David Porcelijn - or indeed any work of serious import, range and impact. Context is the key.

Now, fair play to the BBC for televising Cage at all and hurrah for the happenings in the foyer, the mushroom garden, the films and talks and a wonderfully positive atmosphere throughout. But "Cage in his American Context" was a frivolous and disjointed event that lumbered awkwardly from the Connecticut cow-pat of William Schuman's New England Triptych, through Cage's pristine, electrifying The Seasons, and on to Henry Cowell's Piano Concerto: an experiment that caused outrage in 1928 but now seems pointlessly provocative. Punching a keyboard in protective mittens might make for an unusually bracing aural experience but if atonality clings to the contours and dynamics of the late 19th-century concerto, it's nothing more than mashed-up Rachmaninov. Ives's Central Park in the Dark - the earliest work in the programme but, 4'33" aside, the most radical - was the only piece to warrant the titular context of Friday's concert, and jolly well played it was too under conductor Lawrence Foster.

Impressive as pianist Philip Mead's command of the Cowell appeared to be - who can tell? - the best solo contributions to "Cage Uncaged" were yet to come. Ralph van Raat's account of the Concerto for Prepared Piano with the London Sinfonietta on Sunday was masterful: unshowy, sensitively shaped, nuanced and alert. (The Sinfonietta's performance of Feldman's Madame Press Died Last Week at Ninety was similarly sublime.) Deborah Miles-Johnson's performance of Copland's In the Beginning - caught on radio on my way to see van Raat - was radiant and tender, and Loré Lixenberg brought the house down on Saturday night with Aria: Cage's wittiest and most virtuosic multi-lingual vocal work, scored for amplified voice and whatever else might come in useful. Here it was a television, a vacuum cleaner, a camera, a packet of crisps and the sassiest, funniest and riskiest stage presence around. Ecco la diva! She should have been on the telly.

a.picard@independent.co.uk