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Introduction DED-8420 User Manual (Iss. 01)
Overview
The DED-8420 is a Dolby
®
E/AC-3 decoder with Sample Rate Conversion (SRC) designed for
broadcast use. The DED-8420 takes a Dolby encoded signal and breaks it down into discrete channels,
which are presented at it’s output as AES signal streams. It also extracts the meta-data embedded in
the input audio signal and presents this on the meta-data output.
The DED-8420 card accepts Dolby E, AC-3 encoded or PCM input signals and supports audio
sampling frequencies from 30kHz to 48kHz. Cable equalization and reclocking techniques enable the
DED-8420 to recover the incoming digital audio signal reliably.
When the incoming signal is Dolby E, the DED-8420 outputs the decoded AES pairs as follows:
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AES out1: Left, Right
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AES out 2: Center, Low Frequency Effect (LFE)
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AES out 3: Left surround, Right surround
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AES out 4: Secondary Audio Program
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AES out 5: LoRo (conventional Stereo pair) or LtRt (surround encoded stereo pair).
This is user selectable.
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AES out 6: Copy of input
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MDATA: Metadata
When the incoming signal is AC-3 encoded, the DED-8420 outputs the decoded AES pairs as follows:
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AES out1: Left, Right
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AES out2: Center, Low Frequency Effect (LFE)
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AES out3: Left surround, Right surround
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AES out4: Nothing
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AES out 5: LoRo (conventional Stereo pair) or LtRt (surround encoded stereo pair).
This is user selectable.
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AES out 6: Copy of input
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MDATA: Nothing
If the input is PCM, the DED-8420 functions as a 1 x 3 Distribution Amplifier. The outputs are as
follows:
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AES out1: Copy of input
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AES out 2: Nothing
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AES out 3: Nothing
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AES out 4: Nothing
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AES out 5: Copy of input
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AES out 6: Copy of input
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MDATA: Nothing
The DED-8420 is fully compliant with all openGear technical specifications and DashBoard Control
System™.