English Chamber Orchestra/Christian Zacharias | Barbican Hall, London

Any composer would be well pleased to produce a single piece that matched the perfection of the Mozart piano concertos. Mozart himself could compose six of them in a year. Whatever the creative freakery behind it, the music he wrote when he was 28 makes for a concert series of non-stop peak experiences. As played by Christian Zacharias directing the English Chamber Orchestra, it is shaping up as one of London's best sustained concerto encounters for a long while.

The ECO has had the music at the heart of its repertoire all its life and has played it with several generations of top soloists, but the deft touch, expressive power and rapid-response brilliance of its relationship with Zacharias goes beyond anything that even this mix of hand-picked woodwind and single-minded strings has done for Mozart.

It's as absorbing to watch as to listen. The interaction has the pace, focus and intimacy of chamber music, and that's before the real chamber pieces that round out the programmes. Zacharias, a Prussian born in India and trained by French and Russian pianists, leads with his ears and his fingers.

When he plays alone, the alertness and vitality of response causes an illusion of creating the music there and then. When the ECO's wind players are in dialogue with him it's a feast of practised wit and expressive reinforcement. This ensured that one of the high points of the first two concerts was the Quintet for piano and wind, an orgy of sensual melody and tone colour. Pick of the concerto performances was in some ways No 17, the best known with its extremes of sheer fun and sudden desolation, all profoundly explored with the lightest of touches.

Then again the rather rare No 16 was a particular treat since the musicians characterised it so vividly. But every one of these pieces has strokes of imagination that just stop you in your tracks, and all the performances had something special. In Concerto No 18 it was the quietly tragic end of the variations, in Monday's Violin Sonata the way Stephanie Gonley's broader phrasing complemented Zacharias's fine-drawn detail. In short, as far as the classical tradition goes, this is as good as it gets. So where was everybody? By Wednesday the audience had grown, but it's an advance warning to the Edinburgh Festival - where Zacharias is playing the entire cycle of Mozart piano concertos - that they might need to turn up the marketing heat.

Final concert: Barbican Hall, 13 April, 7.30pm