Cage’s approach to composition was experimental, more concerned with philosophical ideas than with harmony. So, it was curious that, late in life, he took an interest in choirs—though what he wrote for them, during the 1980s and ’90s, was spectacularly off-the-wall. Much of the music on this beautifully produced recording has the stasis of a mindful meditation track or sounds as if composed for a film evoking the void of outer space. The two longest pieces are more active. Hymns & Variations rewrites two American-Colonial hymn-tunes into half an hour of bell-like vocal chiming; while Four6 is an extended riff on noises (chirping, howling, laughter, and more) chosen by the singers and delivered here with absolutely jaw-dropping virtuosity by the Latvian Radio Choir. Surrender, and potential chaos turns ecstatic.