There were several institutions on stage for this concert of Bach cantatas. The Purcell Quartet, now well into its third decade, had teamed up with four singers with similarly long-lived careers. With the ensemble's basic lineup of four players augmented to 13, the superstitious might not have been surprised at the result.

Bach wrote these three cantatas during his early professional posting at the Weimar court; they were performed here according to the principle that their choruses might be sung one voice to a part. Those choruses, and the arias and recitatives too, were dispatched with professionalism, but with nothing like the polish you would expect from a group about to head into the recording studio for the third disc of a series. Add some stubborn and serious tuning problems in this hot hall, and nobody was doing themselves or Bach many favours.

There were high points, though. A trio of deft valveless trumpets vied with Peter Harvey's firm baritone in the first aria of the cantata no 172, Erschallet, Ihr Lieder; the long introduction to no 182, Himmelskonig, Sei Willkommen, sounded beautiful, violin and flute weaving above plucked strings; and Harvey and the tireless tenor Charles Daniels were responsive duet partners in no 21, Ich Hatte Viel Bekümmernis.

But the upper voices came over less well. Emma Kirkby, whose soprano only fleetingly echoes its former pearly resonance, was wisely heard only in ensemble. More surprisingly, countertenor Michael Chance was on shaky form, and looked even less happy than he sounded.

It feels hideously ungrateful to write this way about some of the people who, 15-odd years ago, first opened my ears to vivid, vibrant baroque music. Yet it can't have been gratitude that drove the enthusiastic audience reception at the end - more like pure nostalgic goodwill.