Curiously, in 2,000 there was a newer Hells Bells video series produced. It was much better than the original. It also did not have anything in it about backmasking. Why?
As far as I know of, there is no evidence that backmasking has any effect upon the hearer. In fact, there is no evidence that it is even heard since the brain is designed to decipher things in the forward order, not the reverse.
I think that trying to expose satanic workings in backmasking does little if any good. If artists wanted to say something, they have no reason to hide communications secretly in a backwards fashion. There is plenty of blatanly satanic lyrical content in so many bands' music out there that it would be a waste of time and money to hide messages backwards in their music. In fact, if you were to take any conversation and record it, then play it backwards, you would be shocked to hear all of the strange backwards messages that you yourself spoke. Some of it would inevitably sound like satanic messages. This could even be used as a gimmick to promote a charlatan "deliverance ministry." A simple recording device could "prove" demonic possession in anyone.
My point is this: why don't we Christians focus on the things that the Bible does instead of so many perceived threats to God's kingdom? God is not threatened or circumvented by any music, forward or backward. The themes of lyrics can have an impact on the listeners, to be sure. But to focus on some sparsely scattered messages "secretly" recorded in reverse is nothing short of a modern day witch hunt. There are a number of reverse recorded messages out there. Most of them are admittedly inserted as either poking fun at people looking for such messages or they are inserted for creative purposes and are not satanic in their content. The most infamous backwards messages are mostly random sounds that, if you try really hard, can sound like satanic messages. If I have great difficulty understanding these messages in reverse, how am I supposed to decipher them when the music is played forward in the normal fashion that we listen to?
I remember an urban legend that was going around when I was a kid in the early 80s. The idea was that if you read the whole Bible backwards (You deserve some credit if you can do this. Or at least you have a lot of time to spare.), or played a recording of the Bible backwards, you would invoke Satan and demons. How silly. I have personally experienced a few demonic disturbances that I believe were directly associated with some of the music that I was playing at the time. But these were blatanly blasphemous, vile songs being played. I never had anything unusual occur when I was playing Stairway to Heaven, Queen or anything that was not blatantly and purposefully blashemous. I had things happen three times. One time I was playing "Meat Sandwich" by Gwar. Once time I was when I was playing a particularly blasphemous G G Allin song on my stereo, which will remain unnamed. The other time was at a concert for Neuroses, a very anti-christian, occultic band. My point is that these had nothing to do with alleged backmasking. FYI, I have since turned to the Lord and expunged all of that music from my house and my life years ago, so no need to encourage me to seek deliverance or anything but thanks anyhow.