Conductor Kirill Karabits has a parallel life as a musicologist, specialising in the forgotten music of the late German baroque. He has already unearthed a long-lost opera by Telemann, and he's now resurrected one of Carl Philipp Emanuel Bach's passion settings from 1784, based on a manuscript that only came to light in Kiev a few years ago. The performance of the St John Passion that Karabits conducted, with the BBC Singers and the Bournemouth Symphony Orchestra and nicely timed for CPE Bach's tercentenary this year, was likely to have been the work's first airing since the late 18th century.

During his years as director of music in Hamburg, Bach produced 21 passion settings. Strictly speaking they are compilations rather than compositions, with only a portion of each score freshly composed. His 1784 John Passion derives from one Telemann (his predecessor in Hamburg) composed almost 40 years earlier; that provides the evangelist's narratives and the chorales, with Bach adding some arias and choruses of his own, either brand new or arranged from existing pieces.

It's not a hugely significant rediscovery by any means, though it does epitomise CPE Bach's historical position on the cusp between the baroque and classical eras, with Telemann's solidly baroque setting mingling with the much freer, galant style of his contributions. The whole story is told in barely an hour, and Karabits made sure it was always brisk and concentrated, with Robin Tritschler as the tidy Evangelist and the other soloists coming from the ranks of the BBC Singers; Michael Bundy as Jesus had the largest role, and the best arias.

The passion was prefaced with music by both of its composers – Telemann's short Easter mass on the chorale Christ lag in Todesbanden, and Bach's choral setting of a Klopstock ode and one of his string sinfonias, which did let the Bournemouth Symphony off their leash, urged on by Karabits.