This refers to the process where a DJ is building up to 'Dropping the Bass' in their mix while performing at a nightclub, but then doesn't follow through, and leaves the entire dance floor feeling thoroughly unhappy and unsatisfied.
Guy: "Oh, here it comes! He's about to drop the ....Eeargh! No! that DJ just gave me Nightclub Blue Balls !...My night is ruined"
by Krabooji September 25, 2012