Hellhammer: Satanic Rites demo - 1984
Ah, Hellhammer. One of the big three of early black metal along with Venom and Bathory. Basically they just sped up Venom with a little hardcore punk, dirtied it up further with some delightfully abysmal production, and came up with one of the most influential rackets of all time. There was no subtlety to be had with these guys. The best they could manage was to slow down and hit you with a long, doomier version of their faster material, which of course ruled. After an EP they would break up and continue on as Celtic Frost and history knows the rest. I'm not the biggest Frost fan, since at first they were basically just trying to make Hellhammer sound respectable. Hellhammer do not sound respectable, nor should they. They made ugly, primitive noise that doesn't need to be improved.
So if you'd like to annoy your parents and let them know what a moron you are at the same time, then you could do worse than to blast some Hellhammer.