The "Missa sopra Ecco sì beato giorno" is probably a parody mass, i.e. one based on a pre-existing polyphonic work, in this case named "Ecco sì beato giorno". However, no song of this name has yet been found: it may be a lost work of Striggio himself, or may even be a reference to his similarly titled 40-voice motet "Ecce beatam lucem". The repetition of musical phrases at certain key points in the Mass suggests use of the parody technique, but it has also been suggested that parts of the mass are "contrafacta" – music originally written with different words.