“Is it live or is it Memorex?” was an advertising slogan for the Memorex cassette tapes brand from the 1970s—1980s. This is the brand that claimed to offer an authentic capture, representation, and playback experience. A listener wouldn't be able to tell if they were listening to an actual conversation or performance or if it was a Memorex audio tape, simply being played back on an audio device.

In the 1970s, the Leo Burnett ad agency in Chicago, Illinois had an imaginative idea for selling Memorex's new line of blank cassette tapes. They took and proved the old myth that an opera singer could shatter a wine glass with a high note. Next, they claimed a Memorex cassette had such exacting sound precision that its recording of the singer could break a glass, too.

TV commercials were made, featuring opera singers. The tagline was: "Memorex Recording Tape ... Reproduction so true it can shatter glass". It was soon decided however that the glass-breaking cassette campaign needed a spokesperson whose musical style embodied a more casual brilliance.

Ella Fitzgerald (April 1917—June 1996), the jazz legend and gold standard for vocal excellence, took on the advertising campaign task. She was a paradigm of high fidelity sound.

She had been dubbed “The First Lady of Song” and was one of the most popular singers in the US. As an icon, her singing was loved for more than 50 years. In her lifetime, she won 13 Grammy awards and sold over 40 million albums. Her voice was ageless.

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