To her audience, Janis Joplin has remained a symbol, artifact and reminder of late Sixties youth culture. Her popularity never derived from her musical ability, but from her capacity to link her fantasies of freedom and immortality with ours.

As a performing group, the Beatles began by playing old rock favorites, for dancing, to tough audiences in Liverpool and Hamburg. When they began writing seriously, they discovered that they couldn't compose in the early American rock tradition.

'Call Me' is not an exceptional Al Green album, but it is as solid as a rock at its center.

Elton John can be a master of the sleight of hand. The arrangements make it seem like there are substantial melodies underneath the tracks - but almost nothing demands repeated listenings. Similarly, he always sounds like he's singing up a storm, but his voice glosses over the material, reducing most things to an uninteresting sameness.

In the end, the sign of Aretha Franklin's artistry is that she always leaves her mark - first, on the music, then on us.

'Band on the Run' is a carefully composed, intricately designed personal statement that will make it impossible for anyone to classify Paul McCartney as a mere stylist again.

Bob Dylan was the source of pop music's unpredictability in the Sixties. Never as big a record-seller as commonly imagined, his importance was first aesthetic and social, and then as an influence.