Celestial Sirens is a South Coast-based amateur and semi-professional women's voice choir, formed in 2002 by Musica Secreta director Deborah Roberts. Ranging in size from eight to thirty singers, depending on the project, Celestial Sirens performs plainchant and polyphony from six centuries of choral repertoire.
Although Celestial Sirens gives concerts on its own, one of its primary functions is to extend Musica Secreta's ability to explore the repertoire available to early modern women, particularly in relation to convent music. Thus, the choir has given performances of devotional and liturgical music associated with nuns, ranging from the monophonic song of Hildegard of Bingen through the searing Renaissance polyphony of Josquin and Palestrina to the glittering Baroque magnificence of Chiara Margarita Cozzolani's polychoral Vespers.