From, what many consider their best album, Warrior on the Edge of Time, Magnu is based on a poem by Shelley. Technically its brilliant, and borders on Prog Rock with its classical allusions. Only Hawkwind can have a violin riff that can challenges the guitar riff in a song.
Here is Hawkwind, broadening their sonic palette (oh dear), but they are thankfully still in space. This is a great opening track, and features the only example I can think of of a psychedelic sax solo.