Ainur is a new italian band made of 18 members inspired by Tolkien, whose music portraits Tolkien's writings with his fantastic world of tales and fantasy. Ainur get their inspiration (and their name) from "The Silmarillon", Tolkien's whole life work. The idea of Ainur is to transpose into music the entire corpus of tales of "The Silmarillion": given the extent of the work, both in length and content, they started to put in music sagas or specific tales across different periods of the Three Tolkenian Ages and Ancient Times.
Some comparisons could be found in MANDALABAND project by David Rohl (Eye of Wendor, in particular - 1978): a fantasy-like concept album recorded with the contribution of many artists. A similar "commercial" vein, the same serious prog tendency and evocative atmosphere.