The performances are exemplary, with an urgency and conviction that reinforces the nature of these works as mini-dramas of distilled potency. The singers tear into the dialogues and choruses with a perfect equilibrium of passionate warmth and gleaming purity underpinned by a generous ensemble of instruments with a rich continuo – hugely imaginative playing exploiting sonority and texture – the lament of souls in purgatory, a toe-curling delight of dissonance and suspensions.