Line Inputs
The ACM120XL includes 8 line (auxiliary) inputs. The line inputs are via dual RCA connectors per
channel. Although the ACM120XL is a mono amplifier, dual RCA’s are provided to allow for easy
connection to domestic or professional line sources. The line inputs are suitable for a wide range of
products including tuners, cassette decks and CD players. As the output signal from line sources can vary
immensely, four sensitivity settings are available per line input. These settings are adjustable via dip
switches 1 and 2 per channel. The options are:
Dip Switch 1 off, 2 off
90mV at 47K ohm
Dip Switch 1on, 2 off
9dB pad (cut)
Dip Switch 1off, 2 on
12dB pad (cut)
Dip Switch 1on, 2 on
15dB pad (cut)
Dip Switch 3 is for the XLR microphone input and switches phantom power on and off (see “Microphone
Inputs”).
Simultaneous Use of Mic and Line Inputs Per Channel
The AMIS120XL has 8 microphone and 8 line inputs. In most situations only the XLR or the dual RCA’s
would be used on a particular channel. In some circumstances however, more channels may be needed in
which case both the XLR and RCA inputs can be used simultaneously per channel. When using both a mic
and line input per channel, both inputs are mixed and are controlled simultaneously via the channel level
control.
Line Input Sensitivity
Four sensitivity adjustments are provided for each line input. See “Line Inputs”.
Phantom Power
15v DC Phantom Power is selectable per XLR microphone input. See “XLR Microphone Inputs”. Phantom
Power should only be used on balanced electret microphones. Using phantom power with unbalanced
microphones may damage the microphone.
Muting
The AMIS120XL includes an advanced priority/muting system which is installer adjustable. When
shipped, the AMIS120XL has three priority inputs. From the factory, Input 1 has overall priority and mutes
inputs 2-8 when signal is present. Input 2 has secondary priority and mutes inputs 3-8 when signal is
present. Input 3 has a third level of priority and mutes inputs 4-8 when signal is present. Inputs 4-8 have no
priority and are mixed. All muting in the AMIS120XL is activated by signal (VOX) whether it be on the
XLR or RCA inputs.
A number of muting options are available and can be altered via a series of internal links located on the
front mixer board behind inputs 1and 2.
Muting for any of the first three inputs can be disabled. The muting circuit of input 1 can be disabled by
moving the jumper labelled JP1 (located on the front mixer PCB behind input 1 and 2’s level controls).
Simply move the jumper towards the back of the chassis to disable muting from input 1.
To disable muting from input 2, simply move jumper JP2 towards the back of the chassis.
To disable muting from input 3, simply move jumper JP3 towards the back of the chassis.
Another feature of the muting circuit of the AMIS120XL is the ability to have inputs 1 and 2 on the same
priority level. This is handy for situations where phone paging and microphone paging (for example) are of
equal importance. In this mode, both inputs can be used at the same time and both will mute all remaining