Des will speak for herself, but allow me a couple of 'background' observations.
Methinks that you have read far too much of the "modern liturgical" literature which sets up a false dichotomy: that one can either 'participate' or 'listen.' To one degree or the other, this dichotomy has been used to browbeat otherwise well-meaning people into "sing, jump, say, repeat, shake, rattle, and roll" activities---none of which are necessary.
The phrase "actuosa participatio" used in the VII document on the liturgy does NOT mean "active participation." Rather, it means a metanoia--conforming one's mind to the action of Christ in the Sacrifice of the Mass, and His prayer life.
This 'conformance' allows for several possible routes, among them being intense prayer (with the priest simply by following the text he reads,); one's own self-offering at the Offertory; and thanksgiving after Communion.
Now the nature of genuine liturgical music is "that which elevates the minds and hearts of the Faithful to God" (Pius X.) In brief, this music MUST: 1) use acknowledged 'sacred' texts (eg from the Scripture or text of the Mass;) 2) be 'holy, beautiful, and universal' (also Pius X) and 3) thus be truly art.
Properly speaking, then, this music SHOULD transport the listener (who listens actively--thus participates actively) to God, or at least FROM the world.
Therefore, liturgical music as defined above, serves the purpose of encouraging or helping the listener "to raise his mind and heart to God."
In fact, this IS ACTIVE PARTICIPATION, or conforming one's mind to the Mind of Christ, as Beauty is an attribute of God.
Please pardon me if this is a bit abstruse, but it is important.
It is also important to know that the church choir serves BOTH as representatives of the laity AND as representatives of the angelic choir (cf. Ratzinger and Pius X, Pius XII.) Thus the choir (and delegated singers therefrom) are singing not only 'for' you, in which activity you can join mentally, but 'to' you (eg at the Sanctus, which is a DIRECT quote from the angels' words as recorded in Scripture.)
All to help YOU "lift your mind and heart to God."
SO much for false dichotomies.
Now the nature of genuine liturgical music is "that which elevates the minds and hearts of the Faithful to God" (Pius X.) In brief, this music MUST: 1) use acknowledged 'sacred' texts (eg from the Scripture or text of the Mass;) 2) be 'holy, beautiful, and universal' (also Pius X) and 3) thus be truly art.... where music often devolves into various renderings of Puff the Magic Dragon and where the assembly is often asked to sing along but the three part harmony is tough for us non-musically inclined :-)