Maria Cristina Kiehr’s is one of the most beguiling voices to be heard today. Of a handful of recordings she has made, this disc perhaps makes that point most eloquently because no artifice (whether compositional, stylistic, or vocal) gets in the way of her instrument. As in so much music for Holy Week, the simplicity of the idiom is pared down to essentials. Even the advisability of ornamenting the lines is in doubt. If you suspect that liturgical propriety wouldn’t have stopped 17th-century sopranists from showing off, you may regret that Kiehr plays it quite so straight; but then again it leaves her nothing to hide behind, which poses a challenge of quite another order. Every note dead centre, each phrase thoughtfully shaped: Kiehr convinces you that no more is needed. Need I say more?

Just a little, then. Kiehr is well served by Concerto Soave, whose contribution is successful because unobtrusive. They follow the music’s lead in leaving Kiehr centre-stage, but a few instrumental pieces give them free rein. Those who know Kapsberger’s wild invention won’t be disappointed; a rarer curiosity is the contemporary arrangement for viol of a Palestrina original. But the other star of the show is another “instrument”, an astonishing claviorganum (a harpsichord coupled with a chamber organ) whose two-toned timbre is perfectly attuned to the prevailing acoustic and sound recording.