Specifications

Technical Services: 800-283-5936 19
CHAPTER 2: EXPANSION BUS & LCD PROGRAMMING
EXPANSION BUS
The Converge Pro Expansion Bus (E-bus) allows you to connect multiple Converge-Pro units together to create
powerful audio and conferencing solutions for any size venue. The E-bus is a proprietary digital audio bus that
provides control and audio data links between Converge Pro devices.
Expansion Bus Connections
Using the Expansion Bus Link In and Link Out ports, you can connect up to eight Converge Pro 840T/880s and 16
Converge Pro TH20 units, where the total number of microphone inputs does not exceed 64.
Connect Converge Pro units in daisy-chain fashion (as shown below) using the 18” patch cable included with each
unit (Part # 830-150-004) . For larger distances between units, use CAT 5 twisted pair cable with RJ-45 connectors.
The maximum cable length between connected Converge Pro units is 200 feet (61 meters).
Audio and Control Buses
The E-bus allows audio routing between source devices and destination devices on the E-bus network. The E-bus
contains 12 independent digital audio buses labeled O–Z, which can route mic or line inputs in any combination
across the E-bus network. The E-bus also contains four PA adapt/acoustic echo cancellation reference buses, four
global gating buses, and one control bus.
O–R Buses: These four audio buses are generally used for routing microphone audio between Converge Pro
devices. Information about the number of gated microphones (NOM count) and other relevant information for the
microphone mixers are tracked for microphones routed to these buses. By default, all microphones routed to the O
bus.
S–Z Buses: These eight buses are line input mixer buses. They are used to route auxiliary audio, such as from a
CD player or VCR, to and from other units on the network. These buses are also used as mic mixer buses when
NOM count is not required.
PA Adapt/Acoustic Echo Cancellation Reference Buses: These buses allow an input from a Converge Pro
device to reference an output on another linked Converge Pro device for AEC purposes. See the AEC Reference
and AEC topics for more information.
Global Gating Groups A-D: These buses are microphone gating groups that support First-Mic Priority, maximum
number of mics, etc. and work across all linked Converge devices. Unlike the audio buses, they contain only mic
status and gate parameters. See the Gating and Gating Group topics for more information.
Control Bus: The control bus is an independent channel from the E-bus’s audio channel. This allows control
information to pass even if the units are not using the audio link. Converge Pro devices support the use of the serial
command set through the control bus.