From the Old Testament, the Psalms and Isaiah and Amos. Perhaps a surprise to you that I would add the little work of Zephaniah.
I cannot get over the picture of a God delighting in the gathering in of a remnant who mourn for the solemn assembly. And He SINGS over them. God sings!
Think of all the powerful emotional influence, for good and for bad, that has been wielded by music and song. And the faithful will live in a community of delightful peace, colour, service and music, capped off by the incredible singing of their Creator and Saviour. Heaven it is.