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subwoofer. The outputs of the second subwoofer are connected to the inputs of the third subwoofer and
so on. All “MODE” switches in the subwoofer daisy-chain are set to the “PASS THROUGH” position
except the last which is set to “NORMAL”. The last subwoofer will then apply the bass management
filtering for the loudspeakers connected to its outputs.
When two subwoofers are daisy-chained together in the same system, the in-room sound pressure
level increases by 6 dB, three subwoofers gives an increase of 9.5 dB and four subwoofers gives an
increase of 1 dB compared to a single subwoofer. To compensate for this increase in bass level, adjust
“SUBWOOFER LEVEL” in all the subwoofers in the daisy-chain down to the same level to match the
sound level to the loudspeaker sound level.
Controls selection
The subwoofer works in stand-alone mode when the GLM Control Network is not connected.
The “CONTROLS SELECTION” switch allows selection between two basic methods to control
a subwoofer in stand-alone mode.
“MANUAL CTRLS” refers to controlling the subwoofer using the controls on the subwoofer’s
connector panel.
“STORED CTRLS” refers to using the settings stored inside the memory of the subwoofer. These settings
can be set using the GLM Loudspeaker Manager Software and the GLM control network. The stored
settings provide additional functionality compared to the basic controls on the panel.
When the GLM Control Network is connected, or when the “CONTROLS SELECTION” switch is in the
“STORED CTRLS” position, some of the controls on the subwoofer’s electronics panel may be disabled
(see table below). They are disabled because the subwoofer is being controlled through the GLM Control
Network, or by the settings stored inside the memory of the subwoofer. If a disabled control on the panel
is adjusted, all the lights on the connector panel flash rapidly to inform that the control is disabled and that
the change has no effect.
Selection Switch setting
LFE In
Use
LFE
AES/EBU
Channel
LFE
Bandwidth
Redirect
LFE
+10 dB
Bypass
Mode
Tone
Controls
Subwoofer
Level
System
Level
STORED
Disabled
Disabled
Disabled
Disabled Active
Active
Disabled
Disabled
Disabled
Disabled
MANUAL
CTRL
Active
Active
Active
Active
Active
Active
Active
Active
Active
Active
