Q: Why do some people prefer vinyl to digital recordings?

A: The vinyl-versus-CD tussle goes back a long way, says John Schaffer, director of the UW-Madison School of Music. Vinyl, the format used on 33? rpm LP records, encodes sound as continuous, or analog, waves, while CDs use the digital, one-or-zero code used in computers.

Music, like the signal from an LP, is an analog phenomenon, Schaffer points out, while digital recordings are built of instantaneous samples.

Although vinyl is undergoing something of a renaissance, both analog and digital have advocates, Schaffer says. "There is some truth and some mythology to the preference for vinyl. In the groove on a vinyl record, you have a smooth line that encodes the analog wave. Digital technology has allowed us to eliminate distortion, but that's not always more pleasing. It turns out people like a bit of distortion, which the ear may hear as warmth."

For that reason, digital technology can actually add distortion to the recording, Schaffer says. "There are hundreds of companies producing software or hardware that can reintroduce distortion."