Brahms's German Requiem is not a work that most of us would expect Harry Christophers and the Sixteen to tackle. We think of the Requiem as one of the bigger works of the 19th-century choral repertoire: the Sixteen as its name suggests, is a smallish group, best known for its incisive performances of 17th- and 18th-century music. Brahms, however, capitalising on the work's huge popularity after its 1868 premiere, prepared an edition for small-scale performances that replaced the orchestra with piano duet. This was the version that Christophers and the Sixteen elected to revive.

Ultimately, it doesn't work, though there are gains as well as losses. A small chorus brings with it enormous dividends in terms of polyphonic clarity, in marked contrast to the current fashion for the deployment of vast choirs, where the detail simply vanishes in a kind of aural fog. The piano transcription, however, aims to replicate the sombre colours of the orchestral writing, but all too frequently comes over as a monochrome rumbling low in the instrument. It doesn't ideally suit the Sixteen either, despite the commitment and grace of much of their singing. The tenors were pushed to their limits in the rapturous cries of Selig Sind die Toten in the last movement. As usual, Christophers deployed countertenors as well as contraltos on the alto line - a fine combination in baroque music, though ill suited to Brahms, whose choral writing, intended for women, lies uncomfortably high for countertenors, resulting in more than a few moments of strain.

Its companion piece was Schütz's Musikalische Exequien, effectively another "German requiem", written in 1636 for the funeral of one of the composer's patrons. With its vocal lines endlessly shuttling between the chorus and multiple combinations of soloists, it's hypnotically beautiful, and the Sixteen, infinitely more at ease with Schütz than with Brahms, sang it to perfection.