Composers with an intellectual bent have reveled since the Middle Ages in the creation of music that is mathematically constructed, yet also beautiful. The crown jewel in this category is Johannes Ockeghem’s astounding Missa Prolationum, where four voice parts sing the same line of music, but in four different time signatures, a feat of compositional genius that many believe has never been equaled. This celebration of beautifully crafted complexity also includes selections from Palestrina’s Missa Repleatur os meum, containing canons at steadily expanding intervals; a Missa Canonica by Fux and another by Brahms; a fugue by Bach; and John Tavener’s The Lamb, which employs a haunting twelve-tone motif that is both inverted (upside down) and retrograde (backwards) – a modern echo of ancient technique.