The Musicall Compass/Crispin Lewis; Amsterdam Baroque Orchestra/Ton Koopman, Wigmore Hall; Great Hall, Guildhall, London

On the other hand, the famed Amsterdam Baroque Orchestra and Choir - 27 instrumentalists, 25 voices - under their founder and director Ton Koopman, appearing in the Great Hall of the Guildhall as part of the City of London Festival, proceeded to deliver with a polish and smoothness Bach can scarcely have imagined. The Musicall Compass offered a programme of comparative rarities; the Amsterdam forces gave the great Mass in B Minor BWV 232.

With an expressive, pure-voiced line-up of soloists, a choir of such crisp proficiency and some of the best period players around, the Mass should have sounded exceptional. That it proved anything but was partly due to Koopman himself. It was not just that his speeds were often brisk - absurdly so in the scrambled "Laudamus te" aria - but that his tendency to direct so much of it at one beat per bar created a recurrent sense that the tempo was about to run away, even if it was not.

But the real disaster was the Guildhall itself. Someone in the Festival directorate should have known that this is the worst acoustic in London, reducing all detail to an indistinct fuzz. Agonisingly creaky seats and noisy air conditioning finished matters off.

At the Wigmore, The Musicall Compass had intonation troubles with its Baroque oboes and recorder and wasn't always together under Lewis's beat. But the string section under Huw Daniel proved proficient and, where aspiration and skill came together, as in the vigorous counterpoint of the short Mass in G minor BWV 235 or the jubilant Motet BWV 230, "Lobet den Herrn", there was a real sense of triumph over odds.