Ethernet Hubs And Switches - Meyer Sound RMServer Hardware Manual

CHAPTER 3: CONNECTING RMS NETWORKS
Free Topology twisted-pair technology allows a nearly
infinite number of ways to wire RMS-equipped loudspeak-
ers. However, an individual Free Topology network can
address a maximum of 50 loudspeaker nodes over a maxi-
mum length of 500 meters (1640 feet) using 20 AWG cable
(Belden 8205 or equivalent) and a single bus terminator. A
double-terminator topology allows a maximum cable length
of 1400 meters (4593 feet) when using 22 AWG cable, and
2700 meters (8858 feet) using 16 AWG cable.
Figure 1: Twisted-pair connectors for RMS-equipped devices
To reduce the amount of twisted-pair cabling in an RMS net-
work, groups of neighboring loudspeakers can be daisy
chained. In addition, a twisted-pair cable connected directly
to RMServer can be spliced at a junction box or breakout
panel with multiple outputs that can be patched to multiple
loudspeaker destinations.
NOTE: Multiple RMServers are required if you
want to connect more than 50 device nodes
(loudspeakers, etc.) to a host computer running the
Compass RMS system. This will increase the data
traffic capacity of the network as well as the signal
strength over longer cable runs.
Custom Twisted-Pair Connectors
When designing twisted-pair cable runs, you can use cus-
tom connectors (such as 5-pin XLR connectors) or terminal
blocks to make the installations more user-friendly. This is
common for theater and touring applications.
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Network Terminators
An RMS network terminator is a simple resistive, capacitive
device designed to prevent electrical reflections on the net-
work. Each RMServer contains switchable onboard termina-
tion. If needed, additional terminators can be installed at
almost any location in the network depending on the topol-
ogy used.
Figure 2: An RMS network terminator
Network Repeaters
A network repeater (such as the FTR-120 Free Topology
Repeater from MicroComm DXI) connects multiple seg-
ments of network cabling. It re-times, strengthens, and
regenerates the signal and sends it back to the network. A
network repeater allows you to increase the geographical
coverage of an RMS network.
Figure 3: FTR-120 Network Repeater
NOTE: For information on using the FTR-120
Free Topology Repeater, see Appendix D,
"FTR-120 Free Topology Repeater."

ETHERNET HUBS AND SWITCHES

A hub is a device that joins multiple computers or other net-
work devices to form a single network. Switches are similar
to hubs but are more intelligent; they can inspect data as it
is received, determine the source and destination of the
data, and forward it appropriately. Switches conserve net-
work bandwidth and offer better performance than hubs.
A hub or a switch is needed for RMS networks containing
multiple RMServers, or if you are sharing an existing Ether-
net network connection.