For composer Žibuoklė Martinaitytė, the deep ocean conceals a haunting and hypnotic music that can bring about a feeling of ritual calm; in her words, it inspires a music that metaphorically can “make the darkness visible.” Hadal Zone, written for bass clarinet, tuba, violoncello, contrabass, piano and electronics, seeks to plumb the lower ranges of these instruments, shaping a listening environment that is defined as much by sound and vibration as it is by the musical intent of the composer. Performed by the adventurous Lithuanian ensemble Synaesthesis, and featuring recorded samples of the San Francisco-based choral group Volti (conducted by Robert Geary), the hour-long work takes its title from the scientific name for the region of the ocean that extends below 6,000 meters, where sunlight can never reach. “Darkness as we perceive it is not differentiated,” Martinaitytė explains in her liner notes to Hadal Zone. “The same can be said for low frequencies and low vibrations of sound; what we usually hear is some indistinguishable hum or a murmur, and we mostly feel the palpable vibrations of those sounds through our body.”