In the canon of YouTube videos guaranteed to make you click, videos of people changing a traditionally minor key song to a major key (or vice versa) are somewhere near the top. This irresistible and fairly simple musical alteration has the potential to transport listeners to an alternate universe where “Mad World” could be the theme to a ’90s sitcom, Metallica’s thrashing Kill Em All sounds more like triumphant pop punk, and the theme to The Pink Panther is lame as hell. But sometimes a key change results in a song so vile that it could be used as a torture device in the basement of a Serbian prison. Such is the case with Led Zeppelin’s “Black Dog” played in a major key.