Nathalie Stutzmann. Contralto / Orfeo 55

Contralto by Nathalie Stutzmann shines a light on the deep-voiced female singers of the Baroque era, who were often obscured by the extravagances of the castrati. As she says: "We must remember that the opera composers of the early 18th century saw the female contralto and the male castrato as vocally interchangeable."

Stutzmann's spectacular programme highlights the variety of operatic roles - both female and male - assumed by contraltos like Vittoria Tesi and Anna Marchesini. It includes world premiere recordings of arias by Handel, Vivaldi and Lotti, along with other arias by Handel, Vivaldi, Porpora, Bononcini, Caldara and Gasparini.

The French contralto - here both singing and conducting Opus 55, the ensemble she founded in 2009 - sees a feminist angle to the album. "Even the most brilliant female singers of the Baroque era were overshadowed by men - the castrati, who were idolised by high society. This reminds us once more that women still have work to achieve a form of equality."

Today, a true contralto voice like Stutzmann's has become a relatively rare phenomenon, making Contralto still more of an album to be treasured.