Edgar Froese’s Berlin electronica franchise got into gear with this 1972 double, Tangerine Dream’s third album, the reissue of which highlights their decisive move away from Baader-Meinhof guitars and into gothic liturgies of mellotron and synthesized abstraction. Not that this neuters the band’s still-extant freakout tendency, which grumbles up tectonically to shake the cloud-hung soundscape of cosmic foreboding. Godspeed You! Black Emperor, listen to “Birth Of Liquid Plejades”… This is how you do it, okay?