NPM ... the very very mainatream "big tent" Catholic musician's organization had a whole issue of their journal a few years ago about why praise and worship music is not appropriate for mass. I'd start there.
Although you can work from legislation, I wouldn't.
exactly how broad a range does alius cantus aptus include?)
... those instruments which are, by common opinion and use, suitable for secular music only, are to be altogether prohibited from every liturgical celebration and from popular devotions.
Musicam Sacram, 1967, Instruction on Music in the Liturgy
I designed a new tire tread design which will keep your guitar's tuning more stable
The Church expects pastors and bishops to use common sense
Speaking of the ban on percussion instruments, what is the deal with this?
Oh, you should see B16 in Germany: at some Mass, the musicians started playing smooth-jazz during the offertory, with, I think, a soprano sax as the lead instrument. The papal displeasure was obvious.
Of course the Church would not write a document to forbid P&W music, or any other pop-music trend that comes along. The Church expects pastors and bishops to use common sense and know that styles that imitate entertainment music don't belong at Mass. In a similar way, there really is no need for a document to expressly forbid polka Masses.
But I can hear the rejoinder already: "What is this 'common sense' you speak of?"
"The use of piano is forbidden in churches as also that of all noisy or irreverent instruments such as drums, kettledrums, cymbals, triangles, etc."
While the organ is to be accorded pride of place, other wind, stringed, or percussion instruments may be admitted into divine worship in the United States of America, according to longstanding local usage, in so far as these are truly suitable for sacred use, or can be made suitable.
VI Organo ed instrumenti musicali.
19. È proibito in chiesa l’uso del pianoforte, come pure quello degli strumenti fragorosi o leggeri, quali sono il tamburo, la grancassa, i piatti, i campanelli e simili
VI Organ and Musical Instruments.
19. It is forbidden the use of the piano in church, as well as that of light or loud instruments, which are drum, bass drum, plates, bells and the like.
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