Philharmonia Orchestra/Bruggen, Queen Elizabeth Hall, London

In his later years Sibelius used to surprise his friends by asserting that the greatest orchestral composers were not, as they might suppose, Berlioz, Wagner or Richard Strauss, but Mendelssohn and Mozart. Listening to this all-Mozart programme from a pared-down Philharmonia Orchestra under that veteran authenticist Frans Bruggen, one could hear what he meant.

Although the Symphony No 36 in C K425 Linz uses two trumpets and drums, it requires no clarinets, only pairs of oboes, horns and bassoons - to which even the culminating Symphony No 41 in C K551 Jupiter adds only one flute. And the Sinfonia concertante for violin, viola and orchestra in E flat K364 does without trumpets, drums, flutes, clarinets and even bassoons. But how replete, glowing and lustrous the works all sound.

Perhaps the evening took a little time to warm up. Mozart seems to have composed and performed the Linz over just four days in 1783, somewhat under the influence of Haydn. Bruggen secured neat, measured playing from the start. But playing again the second half of the already leisurely slow movement was, perhaps, a repeat too many and only the finale began to lift off in verve and excitement.

From then on, the concert proved a perpetual delight. By the time the ardent and graceful Marianne Thorsen and the soulful and mischievous Lawrence Power - violinist and violist of the Leopold String Trio and Nash Ensemble - had had their youthful, spontaneous way with the Sinfonia concertante, one felt one had lived through a whole sequence of wordless operatic duets running the expressive gamut from flirtatiousness to tragedy.

And while modern instruments were used, Bruggen's insistence on minimal string vibrato and the evident care he had lavished in rehearsal on the phrasing and balancing of every detail in Mozart's richly varied inner-part writing resulted in a Jupiter of quite exceptional clarity and drive. More than ever, one became aware of Mozart's endless ingenuity in permuting and combining the instrumental colours at his disposal to create that uniquely full and radiant sound.