PROMS: Monteverdi Choir, Orchestre Revolutionnaire et Romantique / Gardiner; Finnish Radio Symphony Orchestra / Saraste Royal Albert Hall, London / Radio 3

As expected, John Eliot Gardiner's Beethoven Ninth hit the ground running. The temperature in the hall last Sunday night matched the atmosphere, almost from bar one. What the violins and violas of the Orchestre Revolutionnaire et Romantique thought about standing for the entire performance one can only guess, but it ensured electric playing. Articulation was breathtaking in its clarity; from the stalls, not even the RAH acoustic could blur the edges. The first movement hurtled to its overwhelming, tragic conclusion like a meteorite. Then came the Scherzo: an intoxicating whirlwind of a dance, driven forward by John Chimes's super-rhythmic timpani-playing. The Adagio - almost as fast as Beethoven's alarmingly lively metronome mark - was even more revelatory. Slow movements have often been the weak spots in period-instrument Beethoven; but here the music danced - at one point unmistakably waltzed - with surprising lightness and grace. And there were colours, details, effects of light and shade that have somehow got lost before.

After this, the final choral setting of Schiller's Ode to Joy came as a true consummation. Bryn Terfel's "O friends, not these sounds!" was a thrilling challenge to the heavenly powers that be - and to old ideas of Beethoven's Ninth. For Beecham, this movement "was composed by a kind of Mr Gladstone of Music". Under Gardiner, it was the utterance of a wild visionary: a man who, perhaps, knows that his vision of universal love and brotherhood is impossible, but isn't going to let that stop him. The singing of the Monteverdi Choir made established criticisms of Beethoven's choral writing seem irrelevant. The solo team, with soprano Luba Orgonasova at its head, sang the final quartet with serene clarity - how could one go back to the wobbly, high cholesterol sound of certain past "great" recordings after this? Some die-hard traditionalists will, no doubt. They're welcome to it.

Jukka-Pekka Saraste's Beethoven Eroica the following evening, with the Finnish Radio Symphony Orchestra, wasn't quite in the same league. But it was good enough to hold the attention and raise a tingle or two in the closing pages. Whatever you think of the dogma that goes with the period-instrument movement, it has re-energised Beethoven playing, and made some conductors think again before they tackle these supposedly familiar classics.

Before Saraste's Beethoven came Magnus Lindberg's new Feria, typically full of teeming detail and rich colours - appropriate for a work inspired by Spanish festivals. Lindberg is in the process of rediscovering themes. Good for him; though as yet his sharply distinctive orchestral motifs seem unsure as to whether they generate the musical current or just float on the surface. An interesting new direction, nevertheless. Christian Tetzlaff's playing in Sibelius's Violin Concerto was prodigious in its energy and technical strength. But it takes an exceptional performance to banish a sense of disappointment after the heavenly opening tune - a sense that Sibelius was, for once, playing down. This wasn't it. Nothing here quite compared with the wonders Gardiner put on display in his concert's first half. Of the four Schubert pieces sung by the Monteverdi Choir the final item, Hymnus an den Heiligen Geist, was a little disappointing: an example of what one writer referred to as Schubert's "harmonium style". But Psalm 23 and Gesang der Geister uber den Wassern are unique treasures, and the Monteverdi Choir sang as if they treasured them. What an evening that was.

Radio 3 broadcast repeats: Gardiner concert 2pm today; Saraste concert 2pm tomorrow

Stephen Johnson