When Martin Luther lamented, "The devil has all the good music," he wasn't saying what we think he was saying. We usually take this as: "all the folk music sung in bars and taverns are really catchy but the lyrics are immoral." But this isn't what he meant. Luther didn't associate the devil with taverns; Luther hung out in them himself, and not for evangelistic purposes!
Instead, Luther and the other Reformers associated the devil with Rome, the pope with the anti-Christ. Luther was afraid the beautiful music of the Roman Catholic liturgy would bring people back to Roman Catholicism. Writers like Palestrina put out some hot stuff, not of the catchy, bawdy variety, but truly great and aesthetically beautiful music.
Got this from a Jeff Meyers lecture on church music which was very good. Great stuff on how being in the Spirit means speaking and singing to one another (Eph 5:18ff), and a compelling theology of church music. Check it out.