Mysterium is a requiem, in both tone and scope, elegantly merging Hammock's modern classical and ambient music instincts with choral flourishes inspired by Nikolaï Korniev, Arvo Part, and Morten Lauridsen. Mysterium merges modern classical, ambient, and choral music, and it's of a piece with recent records by Max Richter and Jóhann Jóhannsson. The gorgeous, hour-long collection features contributions from the Berlin mix engineer Francesco Donadello (Winged Victory for the Sullen, Ólafur Arnalds), Peter Katis (The National, Jónsi, Interpol), and the Hamburg orchestrator Roman Vinuesa ("Iris," "Umrika"), who transcribed scores for the Budapest Art Choir.