From a reader:
Father, is it possible to play recorded mp3s of Gregorian chants during Mass? This scenario is based on the following assumptions:
there is no choir available, the existing choir was newly formed and had little time to practice, and/or they are not willing to chant.
No, this isn’t permitted.
As far back as 1958 in the important Congregation of Rites’ instruction De Musica Sacra we find at 60 c:
Finally, only those musical instruments which are played by the personal action of the artist may be admitted to the sacred liturgy, and not those which are operated automatically or mechanically.
If memory serves, there is another more recent document which repeats this prohibition. However, there is a discrepancy. I believe more recent legislation in Masses for Children it is possible to use some recorded music. I think it is a bad idea to allow for that. Someone out there will claim, “there is a child at this Mass, therefore it is a Mass for children, therefore I can use recorded music”.
Recorded music does not substitute for a living human choir or singer. The artificiality introduced is contrary to the concept of our active participation in the sacred mysteries and the action of the true Actor at Mass, who is Christ the High Priest.
That said, recorded music can be played in church for the purpose of instruction in singing. I also recall that it can be used outside church for the sake of processions.
It may be tempting, from the desire to have excellent music, to use a recording. But that’s a no-no, I’m afraid.