Hell Is That Noise

""I don't know what that noise is, and I purposely avoided finding out. I like to think that it's Satan playing a vuvuzela in Hell.""

- The Distressed Watcher

What the hell is that noise? Hell is that noise.

Sometimes, sounds can be incredibly creepy. When you hear them the first time, they may not be that terrifying, but as time passes, they become more and more frightening as they gain more and more relevance. Given time, the sound comes to haunt you, even when you are not anywhere near the source. It doesn't just have to be a sentence, a catch phrase, a song, or even a laugh, it can also be a simple, mundane sound, like the creak of a chair, or a door, the sound of footsteps, the crackle of radio static, the call of a loud little animal, or any one of hundreds of seemingly mundane noises that suddenly take on a nightmarish relevance because of something you heard. This isn't a Brown Note, a sound or image that causes actual harm to a person in a story, but rather a completely mundane noise that, due to context, will terrify you in ways that cannot be described.

See also Hearing Voices, which can also be this depending on what kind of voices they are, and Nothing Is Scarier, which is almost the Visible Silence version of this. Sinister Scraping Sound is an intentional, psych-out type of hellish noise; if a noise foreshadowing a threat is produced by something attached to, or ingested by, that threat, it's The Croc Is Ticking.

Contrast Most Wonderful Sound, and compare and contrast Awesome Music.

Be cautious when adding Real Life examples; this is a YMMV Trope, and we don't need the Edit Wars. And, much like the Nightmare Fuel tropes, everything can be Hellish to somebody.