The choir, in its origins in ancient Greece, served to explain what a solitary performer could not express and offered a mirror for the audience.
For the innovative theater company Carmina Slovenica, the concept of a choir also provides a broader political lens -- to show how an individual can be swept up in the violence of the group.
The Slovenian ensemble has taken the concept to New York with performances of its intellectually challenging "Toxic Psalms" at Prototype, a festival of experimental opera whose third edition opened on Thursday.
"Toxic Psalms" features a chorus of some 30 women, bleakly dressed in dark gowns in a setting that evokes an imaginary world.
In the course of an hour and a half, they touch on contemporary crises from abuses in the name of religion to the war in Syria.
"'Toxic Psalms' is a reflection of the spiritual anguish of today. Through music the project brings out the image of the brutality of man in the name of an idea -- man killing for the glory of his 'psalms,'" director Karmina Silec told AFP.
The choir performs elements of eight works including Sergei Rachmaninoff's "All-Night Vigil," an allusion to Russian feminist punk rockers Pussy Riot who infuriated President Vladimir Putin and the Russian Orthodox Church with a satirical rendition of the sacred work in the cathedral near the Kremlin.