Rear Panel Features
AC Power Inlet
The 3 pin IEC power inlet is located on the bottom left of the rear panel and accepts a standard mains
power lead fitted with an IEC connector.
The inlet is equipped with an in-built AC fuse holder fitted with an 8 Amp slow blow fuse plus a spare
fuse.
Please ensure that the mains power cord is disconnected before attempting to check or
replace this fuse.
Power consumption is 550VA (max).
24 Volt DC Power Inlet
The AMIS250P feature optional 24VDC power to run off a battery back-up if required. This is connected
via the rear terminal strip. The front panel Power Switch will not switch DC power ‘on’ or ‘off’ in DC
operation. In this mode the amplifier is always ‘on’.
Speaker Output Terminal Strip
Located on the top left of the rear panel is the speaker output terminal strip. Reading from left to right, the
connections are:
COM
Common or “-” for low impedance speaker loads (4 ohms).
4
The “+” for 4 ohm speaker loads (use with common)
COM
Common or “-” for 25v or 70v speaker loads (maximum load of 20 ohms at 70v)
25
The “+” for 25v line speaker loads (use with common)
7
0
The “+” for 70v line speaker loads (use with common)
Please ensure that the correct “Common” is used. Low impedance and 25/70v loads can be used
simultaneously but please pay careful attention to the overall speaker load. When used individually, the low
impedance load should be 4 ohms or higher while the 70v line load should not fall below 20 ohms. When
both outputs are used simultanously, ensure that neither output is loaded to maximum.
Gain Control
Located to the left of the XLR input/output is a recessed screwdriver adjustable gain control. The gain
control is an input attenuation control normally used to match the amplifier to a wide variety of input
signals. In essence, the amplifier is designed to receive a 700mv input signal however the level control can
be used to increase the level for lower signals or decrease the level for higher input signals. In normal use,
the gain control is used as a ‘set and forget’ master level control for the amplifier.
XLR Audio Input and Parallel Output
The AMIS250P includes both male and female 3 pin XLR connectors. While the female is normally used
as the input to the amplifier, both XLR’s are connected in parallel so either will work. When signal is
connected to one XLR, the other XLR becomes a line level output allowing the input signal to be
