Sara Mingardo is the headline act but features in only three out of seven chamber duets. The unifying element is the expert accompaniments of Cenacolo Musicale, most usually a trio of theorbo, cello and harpsichord, with some occasional variety of instrumentation. Steffani wrote more than 70 duets, so three of them are the tip of the iceberg: Lea Desandre and Silvia Frigato combine sensitively in Begl’occhi, oh Dio, non più, an accused lover’s imploration for the suspicious shepherdess Clori to stop weeping; Ribellatevi, o pensieri is communicated wittily by sopranos Giorgia Cinciripi and Lisa Castrignanò; there is dancelike zest in Desandre and Loriana Castellano’s playful account of Testimonianza di Fede, even if their voices are a shade strident for such intimately scaled and subtle music.

Mingardo and Francesca Biliotti produce a striking compound of alto sonorities in Lotti’s Crudeltà rimproverata, which smoulders with unfulfilled erotic longing as an unrequited lover bewails the hard heart of the cruel Mirtilla. Lotti’s skill at creating interweaving melancholic lines is to the fore in Mingardo and Castellano’s rapt performance of Querela amorosa. The audible epicentre of the programme is Mingardo’s emotive rendition of ‘Fuggi pur, o crudele’, an aria over a descending four-note ostinato bass from Francesco Lucio’s opera L’Euridamante (Venice, S Moisè, 1654). Gioele Gusberti’s versatile cello takes centre stage in Bononcini’s Sempre piango/Sempre rido; its depiction of quarrelling lovers is sung with bittersweet tenderness by Mingardo and Lucia Napoli (whose part demands several little solo arias). Bononcini’s qualities are done less convincing justice by Castrignanò and Cinciripi’s unsteady intonation, somewhat pinched timbres and rhythmical looseness in Chi d’Amor tra le catene. The revolving door of eight singers is inevitably a mixed bag, but in general these performances confirm the indubitable richness of the repertory.