The Psalms are not just the pedestrian background for the Hours, and the utilization of singing to pray them is a priority:
278. Clearly the psalms are closely bound up with music (see GILH 103-120), as both Jewish and Christian tradition confirm. In fact a complete understanding of many of the psalms is greatly assisted by singing them or at least not losing sight of their poetic and musical character. Accordingly, whenever possible singing the psalms should have preference, at least for the major days and hours and in view of the character of the psalms themselves.
The following underscores the importance of a knowledge of Scripture in being a music director. At least where the liturgy of the hours are concerned, a church musician can’t escape the need to be more than a musician:
279. The different ways of reciting the psalms have been described in nos. 121-123. Varying these ways should depend not so much on external circumstances as on the different genres of the psalms to be recited in the same celebration. Thus the wisdom psalms and the narrative psalms are perhaps better listened to, whereas psalms of praise and thanksgiving are of their nature designed for singing in common. The main consideration is to ensure that the celebration is not too inflexible or elaborate nor concerned merely with formal observance of rules, but that it matches the reality of what is celebrated. The primary aim must be to inspire hearts with a desire for genuine prayer and to show that the celebration of God’s praise is a thing of joy (see Ps 147).