NTi Audio Digirator DR2 - Manual (Page 43)

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Measuring Functions
7. Measuring Functions DR2
Channel transparency testing
The channel transparency test verifies whether the audio and
auxiliary data of a digital transmission channel are transparently
transmitted. The transparent transmission is crucial for non-
linear PCM formats such as surround sound. The verification
always covers both audio channels.
1
2 3
1 Result of the analysis
2 Status of the validity bit
of the input signal
3 Channels status informa-
tion of the input signal
The displayed validity bit 2 and channel
status details 3 are for information only.
They are not part of the transparency
measurement.
Function
The test signal used in the DR2 is a short deterministic noise
sequence. The signal stream applied to the SYNC input is mon-
itored and verified for a 16, 20 or 24 bit correlation.
AES3 transmission format frames
Preamble Auxiliary LSB Audio Data MSB V U C P
0 3 4 7 8 11 12 27 28 29 30 31
<--------- 16 Bit ---------->
<----------------- 20 Bit ---------------->
<------------------------ 24 Bit ------------------------>