a bass party is the name of a party ( at a house or club) where dubstep, drum and bass, house, trap, and other related genre's of electronic music are played. Nothing like the kandi scene at raves, but rather darker and still loaded with beezys. Bass parties are to electro, as heavy metal is to rock :)
"Are you going to the bass party at Temple this week?"
Guy1: "Ask Drew about it. Drew, wasn't that bass party crackin last wednesday?"
Guy2: "fawk yeah. i was zooted folks. and you were making out with that beez."