So what does it say about me that I don't consider much of the music listed as particularly "dark"?
Here are two that are off the scale.
Lou Reed - Berlin
The Amazon.com review describes it perfectly.
Berlin is psychologically grueling and unremittingly dark (scariest moment: "The Kids," which ends with a very long tape of children screaming in terror) ... The big production flourishes hit like a hangover, Reed's voice sounds like he's trying to stave off emotional involvement with his lyrics because it would hurt too much, and the multi-layered textures of "Oh Jim" surge and recede like details of a nightmare. The album takes strength to hear, and rewards it.
Then, there is Univers Zero. My gods how can one describe this music. Here is the cover to "Heresie".
Any questions?
