I'm reading Ray Manzareks book. He said when they first played San Francisco at the Fillmore nobody really knew them and they were booed when first announced because apparently the hippies in San Fran didn't like southern California bands. He says the Grateful dead treated them like shit, wouldn't even acknowledge them and he says when they took the stage they opened with this song "When the Music's Over" and just utterly nuked the audience, just instantly owned them. I can imagine as this song is intense as hell. Listening to Grateful dead and that la di da shit they do, and then to the Doors, wow