Van Der Graaf Generator

The 2:55 to 4:30 stretch of "Man-Erg" will slay you, whether you love or hate 1970s art rock. It's just a gnarly chunk of sound, with Hammill screaming into reverb about freedom and the band stabbing existentialism with a violent staccato tantrum. Hugh Banton then cuts across all this with his saxophone's robo-monster howl. Genesis and Yes are totally cool, but no other prog rock band ever sounded like Van Der Graaf. For further evidence dive into the 23-minute "A Plague of Lighthouse Keepers."