Tone Generator Common (use with one of the 4 tones listed below)
Pre-Announce Chime
Alert Tone
Bell Chime
Evacuation Tone
Note: The minimum impedance (or maximum load) at 100 volt line should be no less than 80 Ohms for the ACM120 and
no less than 160 Ohms for the ACM60.
Speaker (Zone) Output Terminal Strip
Reading from left to right, these screw terminal pairs correspond to the switched 100 volt line outputs and are numbered
6 through 1 as indicated on the front panel of the amplifier. For each pair, the left hand terminal is the 100 volt output and
the right hand terminal is the common.
Phantom Power Button
This button enables or disables the 18 volts DC phantom power which is available on all microphone inputs (XLR’s). The
“in” position indicates that phantom power is on for all mics. The “out” position means that phantom power is switched
off for all mics. Phantom power is required for electret condenser microphones which require DC power to operate. While
some of these microphones can operate from an internal battery, having phantom power available on the amplifier
eliminates the need to regularly change batteries in the microphone. While phantom power is not required for the more
common Dynamic microphones, it will not damage them providing that they are balanced. Do not plug an unbalanced
microphone in to any amplifier or mixer when phantom power is switched on.
Line Output
The balanced XLR line level output provides a maximum of 700mV to allow for connection to up to 6 power amplifiers.
Simply run a balanced cable from the line out of the ACM60 or ACM120 to the line input of the power amplifier. Pin
connections are: pin #1-earth; pin #2-signal (high, +); pin #3-signal (low, -).
Tape Output
Dual RCA output connectors provide a line level output with a maximum of 350mV into 10K Ohms which is ideal for
connection to most standard tape recorders. This output is sourced before the master gain control and as such, the tape
output level is not influenced by the operation of the master gain control.
Microphone Inputs
All four inputs are dual mic/line with microphone inputs being via a 3 pin XLR connector per channel The mic input
sensitivity is 1mV @ 200 ohms. Pin connections are: pin #1-earth; pin #2-signal (high, +); pin #3-signal (low, -). Phantom
power of +18 volts is available on all microphone inputs. Reading from left to right across the rear panel, the inputs are
4, 3, 2, & 1.
Line Inputs
All four inputs are dual mic/line with line/auxiliary inputs being via dual RCA connectors per channel. Line inputs 1, 2 &
3 have an input sensitivity of 75mV @ 47K ohms. Input 4 has an input sensitivity of 300mV @ 47K ohms making it
suitable for high level inputs such as a CD player. Reading from left to right across the rear panel, the inputs are 4, 3, 2,
& 1.
