Pink Floyd: Piper at the Gates of Dawn The father of all British psychedelic recordings, Syd Barrett was unravelling on the debut. His insanity contributed to the unique, groundbreaking themes and sonics of this recording. This recording was innovative and important in the scheme of modern music.

Captain Beefheart: Trout Mask Replica R & B, jazz, avant garde, experimental, you name it and it probably applies to this Frank Zappa-produced album. The recording challenged boundaries and is considered by many to be one of the most important rock recordings of all time.

The Soft Machine: Volume One Psychedelic, jazzy and experimental, The Soft Machine helped define the prog rock genre with this recording and its successor, Volume Two.

Genesis: The Lamb Lies Down on Broadway Peter Gabriel, at the peak of his career, helped create one of the great concept albums of all time. The character Rael, in his own way, is as important as the character Ziggy Stardust in the area where fantasy meets reality.

Yes: Close to the Edge If you ever had a jazz musician complain that rock musicians have no chops, hand them this recording. An opus and one of the only recordings of this type that does not implode on its own weight of self-importance. It's better than Fragile, because on this, the band really just goes off with jaw dropping virtuosity.