Specifications

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MOUNTING
Up to three Mixers and/or Input Expanders will mount side-by-side in only one
rack unit high using the available rack mounting shelf. They may also be neatly
stacked or mounted side-by side on your desk with the available angled desk
mounting kits and/or Horizontal Joiner. Extra knob caps are provided to allow you
to color code the input controls. Yellow, red and green caps are supplied in addi-
tion to the gray and blue caps on the units. To replace the caps, gently pry out
the old cap and press in the new one.
CIRCUIT DESCRIPTION
INPUT STAGES
The inputs of the MX101, MX100 and MX100C are identical. They are designed
around a very low noise and low distortion, balanced and floating input instru-
mentation amplifier. The SSM2017 is one of the latest generations of devices de-
signed specifically for use as a low noise microphone amplifier. In addition to ul-
tra low noise and distortion, it features a very high slew rate of 17V/µs virtually
eliminating slew induced Transient Intermodulation Distortion.
The three preamp input stages can be individually set for gains of 20, 40 or 60dB
for microphone inputs and 0 or 10dB for line inputs using the internal rocker DIP
switches S11, S21 and S31, position 2 (ON for 60dB gain) and position 3 (ON for
40dB) (turn both positions OFF for 20dB gain) for microphone inputs and position
4 (ON for 10dB gain, OFF for 0dB) for line inputs. The preamps will have an input
clipping level of +18dBu minus the selected gain; e.g., -42dBu input clipping at
60dB gain (8.5mV peak), -22dBu at 40dB (85mV peak) and -2dBu at 20dB gain
(.85V peak). The gain should be set such that the maximum microphone output
level is always below the input clipping level. Some shotgun type microphones
are designed for very high sensitivity to give them the necessary reach and can
easily overload a high gain input when used in a close talking application. Set the
preamp mic gain to the lowest usable level to avoid overload or select a micro-
phone with a built-in, switchable attenuator which you can switch in for close talk-
ing use.
The XP100 has a fixed input gain of 40dB for microphone inputs and 0dB (unity
gain) for line inputs. The XP100 is best used with normal studio type micro-
phones with peak outputs below -22dBu (85mV peak).
The MX101 incorporates switchable single pole low-cut 125 Hz filters on each
input to help block wind noise.