Premiered in 2015, Drone Mass now receives a recording following the untimely death of its Icelandic composer, Jóhann Jóhannsson, in 2018, when he was just 48. Described by Jóhannsson as a “contemporary oratorio,” it’s scored for voices, string quartet, and electronics. Setting texts from the Coptic Gospel of the Egyptians, the work sounds at once ancient and incredibly modern, thanks to Jóhannsson’s fascination with the drone, and it inhabits a similar soundworld to the music of Arvo Pärt. Stunningly performed by its commissioners, ACME, joined here by Paul Hillier’s virtuoso Theatre of Voices, Drone Mass is a mesmerizing experience that builds slowly toward the finale, which seems to slither downwards into gentle resignation.