Cobalt Digital FUSION 3G 9901-UDX 3G_HD_SD Up Down_Cross Converter - Manual (Page 22)

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9901-UDX Functional Description
1-18 9901-UDX PRODUCT MANUAL 9901-UDX-OM (V1.15)
Audio Input Routing/Mixing Function
(See Figure 1-5.) The input routing function provides gain and mute controls
for each input signal. Following these controls, selected inputs can directly
exit the input routing function and be applied to the internal bus, or first be
applied to one of four downmixers or flex mixers.
Downmixers. (See Figure 1-6.) Four independent downmixers ( Downmix-A
thru Downmix-D ) provides for the selection of any five embedded, AES
discrete, Dolby ® decoded, or analog audio sources serving as Left ( L ), Right
( R ), Center ( C ), Left Surround ( Ls ), and Right Surround ( Rs ) individual
signals to be multiplexed into a stereo pair. The resulting stereo pairs
Downmix-A(L/R) thru Downmix-D(L/R) can in turn be routed and processed just
like any of the other audio sources described earlier.
Figure 1-6 Downmixing Functional Block Diagram with Example Sources
Automatic Downmixer. Automatic downmixing (option
+ADM ) allows monitoring a selected stereo pair for a user-configurable signal
level threshold. If this threshold is not achieved within a configurable holdoff
time, the automatic downmixing develops a stereo downmix from selected
alternate multi-channel sources (developing an automatic downmix as
described for Downmixers above).
Flex Mixer. The flex mixer is a flexible-structure mixer in which any of 16
summing nodes ( Flex Mix Bus A thru Flex Mix Bus P ) can be applied to any of
the 16 inputs, thereby allowing several customizable mixing schemes. Any
individual input row can be assigned to any of the Flex Mix buses.
Using this scheme, full cross-point mixing of PCM signals can be achieved
within the limit of available Flex Mix buses, and eventually applied to any of
the internal bus channels. Figure 1-7 shows an example of two independent
3-to-1 mono mixers availed by setting inputs (rows) 1 thru 3 to use virtual
flex mix bus
Flex Mix Bus A , and by setting inputs 4 thru 6 to use virtual flex
mix bus Flex Mix Bus B . The Flex Mix A and Flex Mix B virtual outputs can then
be routed over any of the internal bus channels. In this example, because rows
1 thru 3 are all applied in common to mixer node
Flex Mix Bus A , the Flex Mix
Bus A output is the mono-mixed sum of these inputs. The mono mix on the
Flex Mix Bus B node similarly produces a mono mix of input rows 4 thru 6.
Downmix-A(L)
Ls
L
C A
R
Rs
Downmix-A(R)
Embedded Ch 1
Embedded Ch 2
AES Ch 6
Embedded Ch 4
Embedded Ch 5
AES Ch 1 - Ch 16
AN-AUD Ch 1- Ch 8
Embed Ch 1 - Ch 16
To Internal Bus