Wit and wonder of a white knuckle ride Beethoven

Birmingham Contemporary Music Group | Barbican, London London Philharmonic Orchestra | Royal Festival Hall, London

In certain circles it seems to be regarded as a minor miracle that Sir Simon Rattle, artistic director designate of the Berlin Philharmonic, should still be working with the Birmingham Contemporary Music Group. Why? I suppose the assumption is that, having done the honourable thing by contemporary music for many years, and having carved his way to the plum job in Europe, he should be above such things now and able to bask at leisure in Ring Cycles and complete symphonies. This speaks volumes about attitudes to contemporary music; it's "difficult" or "worthy" or - at best - "good for you" like bran or wheatgrass juice. But judging by Tuesday night's lyrical and absorbing concert at the Barbican, no conductor seriously interested in 20th- and 21st-century music would turn down the opportunity to work with this group.

In certain circles it seems to be regarded as a minor miracle that Sir Simon Rattle, artistic director designate of the Berlin Philharmonic, should still be working with the Birmingham Contemporary Music Group. Why? I suppose the assumption is that, having done the honourable thing by contemporary music for many years, and having carved his way to the plum job in Europe, he should be above such things now and able to bask at leisure in Ring Cycles and complete symphonies. This speaks volumes about attitudes to contemporary music; it's "difficult" or "worthy" or - at best - "good for you" like bran or wheatgrass juice. But judging by Tuesday night's lyrical and absorbing concert at the Barbican, no conductor seriously interested in 20th- and 21st-century music would turn down the opportunity to work with this group.

Despite their starry conductor and two respected soloists, the concert was a democratic affair. In a programme as technically demanding as this, there is no room for coasting, no space for preening egos. Rattle has been involved with the infinitely adaptable BCMG from its inception, as has composer Colin Matthews, whose new work, Continuum, was premiered. For the 45 patrons who had purchased £100 shares in this new commission it was money well spent.

Continuum (scored for mezzo-soprano and 23 players) is, in the composer's words, a scena with no definable plot - which sounds worryingly vague. But setting aside the passages that link the framing fragments of Rilke to the two extended poems of Montale, the work seems closer to a song-cycle. Technically it's impressive; the orchestral textures have a water-colour transparency that echoes the tidal shifts of the poetry. The smart, abrupt percussiveness of the double-bass and the struck and plucked piano-wires is artfully contrasted with luminous string and flute writing. The high-mezzo vocal part, sung by Cynthia Clarey, is gratefully written and easily idiomatic, recalling Puccini in its long, elegant lines. But emotionally Matthews's work seemed cool; partly because of the poetry (imagine the resignation of Strauss's Four Last Songs without the optimism), partly because of Clarey's restrained performance, and partly because of an unresolved quality in the music itself - which the brief, surprising passage of recorded sound only served to underline.

Had I heard Continuum at the start of the concert, my impression might have been more positive but I was so engrossed by Krása's Sinfonie für Kleine Orchester that I rather resented the swift progression into the Ligeti and the Matthews. It's a bitter irony that only through recent interest in Entartete Musik has Hans Krása become well-known, and this evocative, highly varied symphony hints at what could have been an extraordinary career had he escaped Prague before Nazi occupation. As it was, he was interned in Theresienstadt (where he wrote Brundibar) then killed at Auschwitz at the age of 45.

BCMG played the three-part symphony with striking colour and razor-sharp detail, making the crawling, shuddering theme of the final movement, Die Läusesucherinnen (The Lice-Pickers) truly disturbing.

The Ligeti Piano Concerto too was expertly, faultlessly played by the ensemble and by Pierre-Laurent Aimard, the finest proponent of abstract piano music. Ligeti throws in so many colours, cross-rhythms, quotations and bastardisations of different styles that the concerto has the listener reeling from a surfeit of largely unpleasant stimulation. It's incredibly clever, incredibly impressive - even beautiful at times - but at no point do you feel that the creator of this ordered chaos is benign. The strongest impression is of a haughty, virtuosic bitterness. Outside of horror films it's a remarkable achievement to please an audience by making them feel disturbed for the best part of 90 minutes, but BCMG will be repeating the whole programme tomorrow night in their home town, so if you can go along, do.

In much the same way, I could have gone home perfectly satisfied after the first half of Sir Roger Norrington's concert of Weber, Beethoven and Elgar with the London Philharmonic Orchestra. Over the past 30 years Norrington has transformed the way that 19th-century repertoire is performed, pioneering the use of Beethoven's original, white-knuckle metronome markings. What is most amazing about this revolution is that his recipe is - like Delia Smith's boiled egg - blindingly obvious; to re-create as far as possible the sound-world of the composer. Needless to say, performances that don't at least nod in cool acknowledgement to historical practice are rare these days. Still, sparks fly whenever Norrington's authentic-instrument aesthetic meets the modern orchestral beast head on and from the first short-bowed vibrato-free notes it was clear that the concert would be nothing if not exciting.

Elgar's broad and, to my mind, over-wrought first symphony was given a lush and intelligent reading. Weber's bumptious overture to Euryanthe bustled along happily enough, a trifle camp in its courtly chivalry but irrepressibly good-humoured. But the vivacity and humour of Norrington's double-act Beethoven with Emanuel Ax is what stayed with me. In Ax, Norrington had the perfect partner for Beethoven's fourth piano concerto. He played the radical unaccompanied first five bars with matter-of-fact humour and dexterity - his fingers as light and easy as the feet of a large man who really knows how to dance. He whizzed up and down the keyboard, punching out the heavily accented off-beats with vibrant energy, each note separate and clear yet joined into a series of wittily-turned sentences that told the story of the concerto in conversation with Norrington and the orchestra. I wasn't totally convinced by the second movement (the dotted-rhythm string motifs were perilously close to French overture style) but I was captivated even while thinking how wrong it was. And this is what I most prize about Norrington's conducting;it is challenging, descriptive, individualistic and witty. To make the familiar new again is a considerable gift.

BCMG, Symphony Hall, Birmingham (0121 780 3333) 15 October