A multitude of evolutions swept across the face of rock in the tumult of 1967, and none was so jarring and unexpected as the stately grandeur of Procol Harum's "A Whiter Shade Of Pale," with its "sixteen vestal virgins, who were leaving for the coast" - on Top 40 radio. There was no precedent for the onslaught of Matthew Fisher's haunting cathedral-sized organ swirls, or the keening vocals of pianist Gary Brooker, who gave gothic voice to the poetry of the unseen group member, enigmatic lyricist Keith Reid. The touring and recording group settled into a brilliantly talented quintet with guitarist Robin Trower, bassist Dave Knights and one of British rock's premier drummers, B.J. Wilson. Procol Harum forever raised the intelligence quotient of rock with their next two albums, Shine On Brightly (with its 18-minute masterwork, "In Held 'Twas I") and A Salty Dog. The stage was set in 1972, for rock's first and arguably greatest major orchestral project, whose evocative "Conquistador" is a dramatic tour de force that has held onto its mystique for four decades. Various personnel changes have revolved around the core of Brooker and Reid, but as their numerous live albums of the past twenty years have proved, the whole continues to be greater than the sum of its parts.