You can't go without these. I've got some and they're fantastic. They've stopped all of those pesky bad vibrations and now I'm only pickin' up good vibrations. Amazing really.
"Bad vibrations make bad sound." True in certain contexts, but certainly not in the case of a little potentiometer mounted on the front of your amp.
When I think of bad vibes, I think of acid trips. While I've never been on one myself, I'm sure that once you start coming down, everything is going to sound bad.