Listen to Requiem, Op. 9: I. Introit online. Requiem, Op. 9: I. Introit is an English language song and is sung by Stephen Cleobury, Choir Of King's College, Cambridge and Orchestra Of The Age Of Enlightenment. Requiem, Op. 9: I. Introit, from the album Duruflé: Requiem, Four Motets, Messe Cum Jubilo, was released in the year 2016. The duration of the song is 3:32. Download English songs online from JioSaavn.