M Box 0E-IA1250, Manual

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8. POWER ON/OFF SWITCH - One, switch. Set to ON position to turn power to the amp ON. Set to OFF
position to turn power to the amp OFF.
9. VOLTAGE SELECT SWITCH - One, switch. Select either 110V-120V or 220V-240V as appropriate for local
AC line voltage. Please confirm local voltage prior to use or making changes to the setting.
10. AC MAINS - One, three-prong socket. Use the supplied 3-pin ground power cable to connect the unit to an
external AC power supply.
11. FUSE - One, replaceable fuse. For 110V-120V/60Hz use a T10.0AL/250V fuse. For 220V-240V/50Hz use a
T5.0AL/250V fuse.
12. RS232 TERMINAL -
One, DB9F terminal. Connect to an automation system or other controller for two-way
communication with and control of the 0E-IA1250.
13. REMOTE BYPASS - One, six position DIP switch. Set to OFF to allow IR/RS232 control of the selected
zone. Set to ON to block IR/RS232 control of the selected zone.
14. ZONE LINE IN - Twelve, RCA jacks. Connect to the L & R line level OUTs on an audio source that is to be
dedicated to a specific zone.
15. ZONE AUDIO LIMITER - Six, push buttons. Press to activates a -20dB input limiter, for both channels, to
help reduce the level of accidental audio peaks and clipping distortion by zone. Leave in the OUT position
to pass audio through unprocessed, press IN to activate the input limiter.
16. STEREO/BRIDGED - Six, push buttons. Sets zone amplifier output to stereo/bridge mode. This switch
works in conjunction with the zone speaker connections and 8Ω/4Ω - 70V/100V switch position.
Please see sections: Zone Speaker Terminal and 8Ω/4Ω - 70V/100V Switch, previous, for important
information.
Stereo - For stereo signals, leave switch in the OUT (Stereo) position. This applies to all connections in
the 8 Ohm/4 Ohm and 70V/100V configurations.
Bridged - ONLY press this button when using the BRIDGE 8Ω connections in a given zone.
CAUTION: In Bridged mode, the amplifier will encounter a load that is about one half of its
actual value. A 4Ω load would therefore be 2Ω to a bridged amp and if the amplifier isn’t
designed to run safely into such a low impedance (which the 0E-IA1250 is not) damage may
occur to the amplifier. DO NOT CONNECT A 70V SPEAKER CIRCUIT WHILE IN BRIDGE MODE.
The output will be 140V, well beyond spec for a 100V system. Any damage to the amplifier
caused by this configuration is not covered under warranty.
17. AUDIO BUS - One, plug-in screw terminal. Mono, unbalanced input. This input will send the Audio IN
signal to all zones switched to Bus using the Line/Bus Trigger IN. It can also send the Bus Audio IN signal
to another 0E-IA1250 via the Audio Bus OUT.
Rear Panel Features