Specifications

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Expansion Bus
The expansion bus is a digital mix-minus bus that is used to connect Converge Pro units. Audio placed on the bus for a
particular unit is not fed back to that unit, but is available to all other units in the system. Audio on any linked Converge
Pro unit can be placed on a bus channel, or taken off the bus and routed to any output of that unit. The Converge Pro
system has 12 digital mix-minus buses with the following default programming.
I–R Buses• . By default, these ten audio buses are the mic mix buses; they can communicate the NOM count
across the network to other Converge Pro units. Otherwise, these buses are identical to buses S–Z.
S–Z Buses• . These eight buses are defaulted as auxiliary mix buses. They are used to route auxiliary audio, such
as telephone audio, between units on the expansion bus. These buses are used as mic mix buses when NOM
count is not required.
Figure 6.2
Expansion Bus Reference Channels
Expansion bus reference channels are not show on the matrix but are accessed when configuring the acoustic echo
cancellers (AEC) or PA adaptive function on each microphone. The expansion bus reference channels provide a means
to receive a reference input for PA Adaptive Mode and AEC from a different Converge Pro unit. For example, assume
four Converge Pro units are linked together. Audio on the first unit is needed as a reference for mics on units 2, 3 and 4
so that the echo canceller cancels the appropriate audio. This is accomplished by selecting the appropriate PA
Adaptive/EC reference from the first unit and placing it on an expansion bus reference and then configuring PA
adaptive/EC references on the microphones of units 2, 3, and 4 to use the expansion bus reference.
Assignable Signal Processing
There are eight assignable signal processing blocks in the Converge Pro 880T/880TA/880/8i and four in the Converge
Pro 840T. Each of these processing blocks include 15 audio filters of selectable types, compression, limiting and delay.
Processing blocks “pre-mix” a number of input channels, process the “pre-mix” and then sends it to an output channel.
This approach provides great flexibility in signal processing and level control. An assignable processing channel is a
good way to create a “master” level control for a group or mix of audio signals. For example, if a room has both
table-mounted microphones and wireless microphones, all the table microphones could be routed to an assignable
signal processing channel, processed, and level-controlled as one combined group independent of the wireless
microphones.
Routing Matrix Routing Matrix Routing Matrix
unit 1unit 2
unit 3
Out 1Out 1Out 1
Converge Pro 880 Unit 1Converge Pro 880 Unit 2Converge Pro 880 Unit 3
Mics 1-8Mics 9-16 Mics 17-24
Up to 12 CP units
for a total of 96 inputs
All mics except 1-8All mics except 9-16 All mics except 17-24
I bus
Expansion
bus