FSR IT-A25-M70 - Manual (Page 5)

5
REAR PANEL
Mute Switch Input:
Provide a dry contact or low leakage open collector closure to
mute the amplifi er. No connection, or an open circuit provides
for normal operation. The IT-A25 amplifi er provides pop-free
transitions in and out of mute mode.
Audio Input:
NOTE: See Option DIP Switch table for proper settings and additional
information.
Connect a balanced or unbalanced audio source to this point.
Unbalanced signals should be connected between “Hi” and “Lo.”
For IT-A25-M70 only:
Connect mono sources to the LEFT audio input terminals
For IT-A25-S8 only:
Connect mono sources to the RIGHT or LEFT audio input terminals.
Master Gain control:
Provides a wide range volume control to adapt to audio source. CW
screwdriver or fi nger adjust to increase gain.
Audio Out:
For IT-A25-M70 only:
Provides a choice of either 4-8 ohm or 70 volt mono output for
fl exibility in interfacing to the room speakers. Connections should be
made to only one output type in a particular installation.
For IT-A25-S8 only:
Provides connection to 4-8 ohm stereo speakers. Outputs may be
bridged (connect + to + and connect - to - When bridging, be sure to
set front panel switch 2 to “mono” mode) to double the output power.
Use 4 ohm speaker, or parallel combination of 8 ohm speaker to
achieve full power when bridging outputs.
Power Input:
Connect to supplied 24 volt external power supply.