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In order to perform ‘click-less’ switching of digital audio signals, a ‘cut’ must be made
during a point in the data stream when no audio is present (usually during a pre-
amble). For this to happen, the switcher must receive a digital audio reference signal
synchronous with the audio signals arriving at the frame.
Note that an audio cut is performed at the first appropriate instant following a
television field boundary (as derived from the video reference input).
The
Freeway
router can be configured to accept an unbalanced digital audio
reference, via the unbalanced AES reference BNC. In this case a ‘dummy’ 9 way ‘D’
type connector and shell, containing two wire links, must be fitted to the AES
reference input connector. The diagram below illustrates the necessary installation
details.
