Orchestra of the Eighteenth Century/ Brüggen, Barbican Hall, London<br></br>La Bohÿme, Glyndebourne Festival Opera, Sussex

Beethoven, Schubert and the dazzling glory of life

In any given week a music critic's job might involve listening to music from up to nine different centuries and at least as many countries. More usually, it involves repertoire from only two or three of these, and a great deal of repetition. If you've seen one Tosca, chances are you'll have seen the next in a matter of weeks. Magic Flutes? Don Giovannis? Like the overture to Weber's Oberon, they come in threes. Brahms's First Symphony? Four in six months is my personal record.

The hazards of over-exposure to the canon are not to be sniffed at. Though familiarity rarely breeds contempt, certain works become "problems" to be solved, and analysing those solutions offered by any particular performance almost inevitably takes precedence to experiencing the work itself. So I often wonder what it would be like to hear, as though for the first time, something you know so well that you can't remember when you first heard it. How would it be to respond to the St Matthew Passion as an 18th-century Lutheran, to be outraged by The Rite of Spring like a pre-war Parisian, to have no notion of what to expect from a then radical, now iconic work or where its journey may lead? Allowing for a programme that moved backwards in time from Schubert's Unfinished Symphony (1822) to Beethoven's Eroica Symphony (1803), for comfortable modern seats and electric lighting, and for a brain stuffed full of dissonances crueller than those imagined by either composer, I feel I have heard the next best thing; the definitive and utterly re-radicalised contemporary performance of both.

Those readers lucky enough to have caught last week's tour by Frans Brüggen and the Amsterdam-based Orchestra of the Eighteenth Century, should - unless totally averse to the thrill of distinct instrumental textures and the clarity of an ever-audible woodwind section - know exactly what I mean. Pre-existing sympathies towards historically informed performance practice notwithstanding, this was an exceptional event. But the Orchestra of the Eighteenth Century, many of whose players today were handpicked from Europe's leading period specialists by Brüggen when he founded it 22 years ago, is an exceptional orchestra. Yes, they face the technical hazards that all players who battle with valveless horns and wooden flutes and gut strings face, but you would never know. (Most notably, not a single back-desk violinist was miming during the many pianissimi in their Barbican performance - which lesser players do - while Eric Hoeprich's clarinet solos were the most ravishing I have heard in this repertoire, period.) Consequently, there are none of the fruity foibles of most period instrument bands; no incidental squeaks or slides or burps or farts. All you hear is this incredible sound - a salty, toothsome, toffeeish tutti spiked with the chilli and basil and lime of brass, woodwind and kettledrums - and the dazzling rush of questions and ideas and statements that Schubert and Beethoven posed in their symphonies.

For Brüggen, whose breathtakingly static, tragic Schubert only deepened the impact of his exuberant, propulsive Beethoven, it would appear that the common ground between the Unfinished and the Eroica is a "Yes!" Where Beethoven exclaims the affirmative, punching the air with his stark, percussive opening chords only to explain in a visionary's urgent whisper that what he means is, "Yes, life is good; life has so much more potential than anyone could have conceived of before the revolution - but you would not believe the pain that you must go through before you can experience this!", Schubert states, "Yes, life is incredibly painful and those flickers of transcendent beauty only worsen the pain through the regret that their inevitable passing brings." At least, that's what I got from Brüggen's account, and prior to this performance, I had only marvelled at structure and sound or the blocked movement-by-movement emotions. Now, I have a picture of grumpy Beethoven running through the streets of Vienna trying to explain his epiphany to anyone whose sleeve he could grab, and a picture of the famously social Schubert desolate and alone.

Of course, there was more to this concert than the possibly fanciful sense of connection to two imaginations at pivotal points in their artistic journeys. (Imaginations naturally altered through Brüggen's interpretation of them, and my subsequent interpretation of that.) More even than the unprecedented feeling of being utterly gripped by an unknown narrative in such completely familiar repertoire. Pathos and heroism were communicated through the finest technical and expressive means. Brüggen's negotiation of speeds made the most audacious extremes of tempi feel natural, his balance of structure, dynamics and detail allowed for the intensification of nuance within an organic whole, the blend of his cello section - a crucial factor in the Schubert - was unparalleled. It was quite the best account of either symphony I've heard; a unique, dramatic, transformative event that will likely spoil me for any subsequent performances. Next time they're back, just book those seats.

Which, depending on the timing of the Orchestra of the Eighteenth Century's next visit, might make for an expensive summer. Although there's nothing particularly radical about the revival of David McVicar's glam-grunge La Bohème at Glyndebourne - the graffiti in Rodolfo's squat is pretty - Bohème offers a generous measure of good, old-fashioned entertainment. Sweet, sexy, lively and open, superbly conducted by Mark Wigglesworth, charmingly performed by Glyndebourne's young cast (some musical lumps and bumps aside - why so loud, Musetta? why so Baroque, Mimi?), this is great fun, with Nathan Gunn's yummy Marcello a walking baritonal antidote to the tenor-tubbies. Not transformative, not particularly tragic even, but if you have qualms about breaking off from a great psychodrama for a champagne picnic, Bohème is just the ticket.

a.picard@independent.co.uk

'La Bohème': Glyndebourne Festival Opera (01273 813813) to 1 July