Is there really any acidic (popular) music before chicago acid? obvs loads of lacerating firing neural synapses early academic stuff.
well all the psychedelic space rock (american, german, japanese, turkish) etc was "acidic" wasn't it? all those rock behemoths from that era - even the biggest of them - pink floyd for instance. you don't get more commercial than that.
as for non technological stuff - i'm forgetting the incredible string band. hangman's beautiful daughter and the debut. doesn't get more acidic.