A friend of mine once said that music was the only "pure" art form. He argued that other forms of art - painting, drama, literature, dance and so on - were representations of reality, whereas music was completely abstract. He noted also that, unlike other arts, similar pieces of music produced similar emotional effects across all cultural barriers.
Curiously, he never had an explanation of why this should be true of a "completely abstract" art form.
Looking back, I don't think music reaches across cultural barriers because it's abstract. I think it crosses barriers because it represents reality at a deeper level.
It's been noted that, in The Lord of the Rings, the Elves spend a disproportionate amount of their time singing.
In Letters #144, J.R.R. Tolkien describes the Elves of Middle-earth as being similar to Men, only "with greatly enhanced aesthetic and creative faculties". He goes further in Letters #181, noting that the Elves have "the artistic, aesthetic, and purely scientific aspects of the Humane nature raised to a higher level than is actually seen in Men... They also posess a 'subcreational' or artistic faculty of great excellence."
Intriguingly, when the Elves use their subcreational powers, they tend to do so by singing.
When Frodo and his companions met one of the early Nazgul it was driven off by Elves, who drove it away by singing. Aragorn, though not an Elf, worked to save Frodo from the Morgul-knife by "taking the dagger-hilt... and he sang over it a slow song in a strange tongue" (Fellowship p. 210). Finrod Felagund's battle of magic with Sauron was fought with "songs of power" (Silmarillion, p. 171 hardback). Luthien threw down Sauron's tower of Tol-in-Gaurhoth by singing, and put Morgoth to sleep by singing, and won Beren's spirit back from Mandos by singing...
In a rec.arts.books.tolkien posting dated 7 May 1996, Bill Thompson once observed this about Tom Bombadil's defeat of the Barrow-wight:
"Also, Bombadil performed his little stunt by singing. Hmmm...there seems to be a recurring theme here. :-)"
Oddly enough, a school of thought is beginning to appear in some scientific circles which states that matter and energy, like music, are frequency-based. If this proves to be true, music might indeed be a way to manipulate the world around us... and perhaps the "magic" of the Elves might have a basis in scientific fact.
Perhaps the Elves know something that we don't.