Often, equipment can as easily function as a security blanket for musicians unwilling or unable to risk anything personal in the studio. Whether one catches the feeling on a record is a subjective matter. How can you be sure? The machinery can hold out the promise of at least mechanical perfection.

'Let's Get It On' is a classic Motown single, endlessly repeatable and always enjoyable.

The Beatles production is often so 'perfect' that it sounds computerized. 'Sgt. Pepper' really does sound like it took four months to make.

The early Bob Dylan was compulsively drawn to the conflict between stability and the search for immortality.

The Rolling Stones are constantly changing, but beneath the changes they remain the most formal of rock bands. Their successive releases have been continuous extensions of their approach, not radical redefinitions, as has so often been the case with the Beatles.

On first listening, Joni Mitchell's 'Court And Spark,' the first truly great pop album of 1974, sounds surprisingly light; by the third or fourth listening, it reveals its underlying tensions.

The modern recording studio, with its well-trained engineers, 24-track machines and shiny new recording consoles, encourages the artist to get involved with sound. And there have always been artists who could make the equipment serve their needs in a highly personal way - I would single out the Beatles, Phil Spector, the Beach Boys and Thom Bell.