In 1973 Tangerine Dream signed with Virgin Records, recorded Phaedra and embarked on the most commercially successful and critically lauded phase of their existence. What made Phaedra different from Tangerine Dream's earlier albums was the use of the sequencer (the band had used sequencers on their previous recording, Green Desert, but that album was not released until much later), a device that was a crucial component of the band's classic style. Take the sequencer patterns out and what you are left with — spacey phrases produced by Mellotron, organs and synthesizers — isn't tremendously different from what the band had already been doing.
With those patterns in place, though, the music takes on a whole different dimension. What had once sounded airy, atmospheric — even free-form — moved with significantly more purpose and drive once locked into that mechanical pulse; by contrast, the passages without sequencers are rendered all the more effective. Nowhere are these new developments more definitively on display than Phaedra's powerhouse title track. Almost as great is "Movements of a Visionary," a piece of similar style that packs in even more of the band's new hi-tech toys. Ironically, though, it's the sequencer-free "Mysterious Semblance at the Strand of Nightmares" that I think is the album's best. With an unexpectedly moving sense of grace, the piece absolutely perfects the "cosmic cathedral" atmosphere that recurred across the band's earlier records.
Phaedra is a landmark album of 1970s electronic music and was also Tangerine Dream's most accessible and "musical" to date. I think that it is the best of the band's first six albums and one of Tangerine Dream's two or three best overall