Couperin’s Leçons de Ténèbres, his sublimely mellifluous and piquant settings of texts for Holy Week from the Lamentations of Jeremiah, are among Baroque music’s greatest treasures, and have received a satisfying flow of recordings in the last decade or two. This one, however, is the first to put them in a spiritual context by setting them among liturgically appropriate plainchants as well as motets by Charpentier and Michel Lambert. All this music is for female voices only – one or two with continuo in the Couperin, a small choir in the rest – as befits the identities of the Leçons’ probable original performers, the nuns of the convent of Longchamp just outside Paris. Extra atmosphere is provided by accompaniment from a colourful French classical organ (the restored 1748 instrument of Saint-Antoine l’Abbaye at Isère) instead of the more usual continuo chamber organ with bass viol. To hear a tremulant stop gently warbling in the “Plorans ploravit” section of the First Leçon is certainly a strange and wonderful thing.

The results have an affecting devotional feel, above all in the gently voiced choral items (Charpentier’s as beautifully written as ever, Lambert’s Miserere less arresting but making a welcome debut on disc here), but also in the Leçons, which, while strongly projected into the spacious acoustic by soloists Dorothée Leclair, Eugénie Warnier and Juliette Perret, are granted more straightforward interpretation than, say, the knowingly sensuous account given by Sophie Daneman and Patricia Petibon for Les Arts Florissants (Erato, 7/97) or the overtly dramatic displays of Johanette Zomer and Anne Grimm for La Sfera Armoniosa (Channel Classics). On another day those rival recordings may stir the blood more, but this one has strongly evocative charms of its own.