Metallica is not metal. I'm talking about screeching or growling into the microphone.
Listen to my link. Growling, yes it's in there but all things considered, it's a pretty good song, no?
It's not fair to lump metal in with the argument that rap isn't music. Metal bands play all their instruments the same way any band does. A lot of it is very technical musically as well. Most of your real metal (I'm not talking about that crap you hear on the radio) is rooted in classical music.
there is shit in all genres. Not all metal is shit, not all rap is shit. But there is shit out there. And some people like shit...either because they don't have the auditory perception to understand it's shit, or because they know someone in the band...lol
usually they will not only use tone but they also use the pauses, and speed as the "musical" part. Instead of frequency being tone like singing, frequency would be speed of the words when it comes to rap.
Take what I say with a grain of salt, because that's all it is compared to the ocean of complexity when it comes to actions and real life.