Although not quite matching the sales figures for Phaedra, Rubycon reached number 10 in a 14-week run, their highest-charting album in the UK.

"Rubycon, Part One", the A-side of the LP, "ebbs and flows through tense washes of echo and Mellotron choirs, as primitive sequencer lines bubble to the surface”.

[3] In contemporary reviews, Chris Salewicz of the NME wrote that the album was "a touch more electronically sophisticated than Phaedra [...] perhaps, and the technological massed choir that floods out of the speakers a couple of minutes into Part Two indicates a considerable degree of carefully wired panache."

"[5] Tom Moon includes Rubycon in his 2008 book 1,000 Recordings to Hear Before You Die, saying: "This voyaging vision of sound, ever-unfolding and not quite ever arriving, has been imitated endlessly since 1975.

"[6] In his 1997 book Digital Gothic: A Critical Discography of Tangerine Dream, music journalist Paul Stump praises the album, noting: “Rubycon is simply a refinement of its predecessor—but to an acme of excellence, and demonstrates a mastery of primitive technology breathtaking in its audacity, tenacity and sheer artistic vision.