P DM 5240 Reference Manual. Rev 2.1
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group 3, however, is not guaranteed to be phase-aligned with the content of
groups 1 and 2 (which had been there before already).
I.e. if the content of the HANC space is re-arranged to accommodate for an additional
audio group while other audio groups remain present, the additional groups are, by
default, not guaranteed to be deembedded phase-aligned to the previous content.
Such phase-aligned deembedding can optionally be guaranteed, even in the above case.
This can be achieved by enabling the Parameter “DeembPhaseSync” on the “Params”
tab (page 25). As a consequence, all deembedding will be re-initialized on a re-
arrangement of the HANC content. In the above scenario, there would be an audible
disturbance in the contents of groups 1 and 2 when group 3 appears in the HANC.
NOTE The Params-Tab contains another parameter with a similar name:
“DeembPhaseSyncVerify*”. This parameter is ON by default and it guarantees
phase alignment within a stereo-pair. This is not the same as guaranteeing phase
alignment across groups, as explained above.
Audio Content Detection
For every input AES channel, the content type is
automatically detected and displayed in the
APPolo GUI by a single upper-case Letter. The
following indications are supported:
P
PCM stream (transparent stereo)
E
DolbyE encoded stream
D
Other encoded data (e.g. AC-3)
<none> If no letter is displayed at all, then this
AES channel does not currently carry
any data.
NOTE: Automatic Content Detection can be overwritten by manual decision (click onto
the box with the letter ‘P’). This is, however, only recommended for testing
purposes. I.e. in order to achieve best possible signal integrity, it is strongly
recommended to leave the Content Detection algorithm in “automatic” mode.
Sample Rate Conversion
A Sample Rate Converter (SRC) is provided per each external AES input stream. The
SRC will re-sample the input to a 48kHz samping rate as derived from the current SDI
source signal. SRCs are enabled by default (checkbox in APPolo GUI is set to active). If
the content type has been detected as anything but PCM (letter ‘P’, see above), then the
SRC operation will automatically be bypassed. I.e. it is NOT possibile to destroy an
encoded bitstream (such as DolbyE or AC-3) by accidentally leaving the SRC activated.
NOTE: If the input AES stream is already sampled at 48kHz, but if that sampling rate has
not been genlocked to the same REF, then the use of the built-in SRC’s is
mandatory to achieve the correct sampling structure for the internal processing.
Figure 11: Content Detection and SRC
