CLASSICAL Lufthansa Baroque Festival St James's, Piccadilly

The career-minded musicologist could happily establish a reputation for perceptive scholarship without ever listening to a note of a particular composer's output, toiling among the archives to become an expert on the same composer's life and times. Joshua Rifkin, whose expertise is most closely associated with the works of JS Bach and the ragtime king Scott Joplin, is a paid-up member of the scholar performer community, one of those rare birds with the ability to test theory against practice and challenge the lifetime performing habits of other musicians. Almost two decades after Rifkin suggested that Bach's choral works were effectively performed using one voice per part, the case for and against is still being rehearsed in learned journals and condemned by conductors who prefer the sound of a "big" choir.

This year's Lufthansa Festival of Baroque Music opened last Friday with the first of two concerts devoted to small-scale Bach, revealing Rifkin's brand of Bach Lite and a more muscular version of the same from Ivor Bolton and his St James's Baroque Players. Differences between the performing styles and approaches of both ensembles were outweighed by the similarities, despite the striking contrast in tonal blend of the respective vocal teams and Rifkin's preferred continuo partnership of cello and violone.

Leaving aside the matter of Bach's use of boys' voices rather than the soprano and counter-tenor favoured here, I was more often puzzled in both performances by the necessity for a stick-wielding conductor. Not that either man did a bad job, since Rifkin and Bolton had a clear idea of what they wanted from the score and were quite able to get it. But in Rifkin's account of the St John's Day cantata Freue dich, erloste Schar, for example, the otherwise accomplished solo team were guilty of ragged phrasing in the central chorale that a group led from the keyboard and required to listen rather than watch would almost certainly have avoided. Later, in the aria "Ich will nun hassen", sung with apostolic fervour by the robust bass Michael Schopper, the presence of a baton waver seemed to inhibit the string playing and stifle the free flow of Bach's contrapuntal lines. I am happy to declare in favour of one-voice-per-part Bach, but would have been even happier here if Rifkin and Bolton, both seasoned keyboard players, had followed the Leipzig master's precedent and directed proceedings from within the ensemble.

It would be impossible to do justice to the soloists employed for both concerts in the space remaining, since each shared an uncommon sympathy for Bach's taxing vocal lines and a willingness to colour and articulate words. Ann Monoyios, Ian Partridge, Mark Padmore and Michael George were consistently fine in their solo arias and as members of the chorus. Watch out for the future rise in the early music world of Lawrence Zazzo, the Philadelphia-born counter-tenor and a former choral scholar at King's College, Cambridge. There is already a touch of James Bowman's beguiling artistry in Zazzo's rich but never forced delivery, put to moving effect in GM Hoffmann's cantata Schlage doch, gewunschte Stunde, and signs of a keen dramatic sense in his interpretation of the echo aria from Bach's Hercules auf dem Scheidewege, enhanced by Gail Hennessy's sublime oboe d'amore playing.

Festival continues to 28 June. Booking: 0171-437 5053

Andrew Stewart