Liturgical prayer contains many elements. Our participation by praying aloud and singing is liturgical prayer. When we dip our hand into the water at the font, a reminder of our baptism in Christ, when we sit in silence, listening to the Word of God, when we walk in procession to receive the Body of Christ in communion, when we lift our hands humbly to receive the Bread of Life and say, 'Amen,' we are praying liturgically. When we serve as a lector, eucharistic minister, choir member or minister of hospitality, we are praying liturgically. Even a simple gesture of standing, bowing, genuflecting is a liturgical prayer.
Music too becomes prayer.
The early Christians were a singing community, whose worship and prayer lyrically co-mingled song and speech. Music connects people. It's sung prayer, and it certainly is a community thing. It enables one to rejoice at rejoicing times. Music sets the mood for worship.