One of the most linked to posts on this blog is in reference to the song Stairway to Heaven (https://briandavidphillips.net/2004/02/stairway_to_hea.html) and how if you play it backwards, you can hear an ode to Satan . . . making it one of the most ingenious pop songs of the twentieth century (heaven one way and hell the other) . . . it's a controversial post yet merely links to Jeff Milner's excellent webpage on backwardmasking - http://jeffmilner.com/backmasking.htm - which has a nifty tool that lets you hear the pertinent bits clearly, or unclearly as the case may be.