The Kalavox sound slide was a system introduced by Kalart-Victor, which comprised a 2×2-inch slide holder combined with a tape cartridge with a capacity of 60 seconds. Up to 40 sound slides were mounted in a special carousel tray that could be placed on a Kodak Carousel projector in place of the normal slide carousel.
Because each sound slide had its own narration, there was no problem with synchronisation, and slides could easily be re-sequenced, or the narration for individual slides changed.
One of its drawbacks, other than the cost, was that the narration could not be duplicated across multiple sets of sound slides, so was limited to one-off presentations.
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