The horn is connected to a smart phone by an external microphone which is strategically placed at the flat end of the horn.
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2.
When the ODJB musicians set up their instruments on Feb. 26, Victor engineers placed the musicians at different distances from the large conical horn that served as a microphone in those days.
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3.
When it refused, Horn tapped it on the nose with a microphone to get its attention.
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