Cloud CXM, Инструкция по установке и эксплуатации

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CXM Technical
MANUAL
8
CM1 Microphone module
3.01 The CM1 module contains a low noise balanced microphone amplifier with line
level switching, a 100Hz high pass filter, 3 band equalisation, line level insert, 2
auxiliary sends, Pan control, PFL select, Peak LED, channel fader and mute
switch.
3.02 The microphone amplifier is an electronically balanced, transformerless design,
configured for optimum low noise performance. The input impedance is greater
than 2k
Ω
and suitable for microphones in the 200 - 600 Ohm range. A gold
plated 3 pin XLR type connector with latch is located on the rear of the module.
To run the XLR input in an un-balanced mode it is suggested that the pin 3
terminal be shorted to the ground terminal (pin 1) inside the cable plug.
The high level line input is electronically balanced with an input impedance
greater than 20k
Ω
. A 3 pole 1\4" jack socket on the rear panel is used for the
balanced line input. If it is desirable to use the line input in an unbalanced mode,
a 2 pole 1/4" jack plug can be used.
3.03 Input select switch
This 2 position switch selects either the microphone input or the line input and
has adjacent LED's indicating the selected input.
3.04 Input Gain Trim
The microphone input can be varied between 16dB and 54dB of gain. The line
level input has a gain range from -4dB to 34dB.
3.05 Phantom Power
Capacitor microphones can be powered by the 48 volt or 17.5 volt power supply.
A circuit jumper on the module PCB is used to turn the power on and off.
Phantom power must not be used on unbalanced inputs and it is good practice
to disable phantom power when using conventional dynamic microphones as a
potential lead fault could load the supply line. The PSU 1040 is factory set for
48V operation and all CM1 modules leave the factory with phantom power
disabled.
3.06 Equalisation
HF (High Frequency)
This control provides 15dB of boost or cut with a 'shelving' response. A switch
adjacent to the HF control selects the turn over frequency of either 5KHz or
10KHz.
MID (Middle Frequencies)
This control is continuously variable between 300Hz and 5KHz, with 15dB of
boost or cut at the selected frequency.
LF (Low Frequency)
A range of 15dB of boost and cut at 50Hz is provided with a similar 'shelving'
characteristic to that of the HF control.
3.07 100Hz High Pass Filter
A 12dB/octave filter operating at 100Hz. This can be effective in removing low
frequency system rumble, handling noise and other extraneous signals, resulting
in a cleaner vocal response particularly when bass boost is used. A yellow LED
illuminates when the filter is effective.