Susan Sharpe introduces another concert from the weekly early music series given at the Wigmore Hall in London. Today Musica Contexta , director Simon Ravens , follow the English cleric Gregory Martin - author of Roma Sancta- on an imaginary trip round some of Rome's churches on Christmas Day around 1580. The music includes Palestrina's Missa Dies Sanctificatus, together with the motet on which it is based, and other Christmas music by Victoria, Silva, Carpentras and Festa.