PreAmplifier / EQ
Mixer Piezo MPU
JB passive
JB active
BPS Circuit
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MX1, MX2 Active Mixer Preamp for Magnetic- and Piezo- Pickups

Low Noise Studio Quality :: High Quality Dustproof Pot.
Rugged and Shielded :: Input Screw Terminals

The RICHTER MX1, MX2 active mixer preamp combines two buffered high impedance inputs via a blend potentiometer to one output.

In the center position - provided by a center click - the input signals have
the same level.
An additional cermet trim pot in channel 1 of the MX2 circuit provides a matching between both input signal levels by attenuation the IN1 signal.
Two screw terminals for easy and solder free connection of signal sources - magnetic- or piezo-pickups are a guarantee for quick and easy mounting inside your instrument - ideal for luthiers and replacement.
This fully shielded circuit requires no shielding inside the instrument.
We use only the best quality components on market available.


  • Low noise, high definition amplifier design with precise and smooth
    sound reproduction without signal losses.
  • Discrete class A input sections with hand selected and matched FETs.
  • 0,1% precision metal film resistors in the signal path with a resultant noise factor of up to 10 times lower than standard thick film resistors.
  • Low tolerance film and COG capacitors in the signal path featuring lowest distortion and superior linearity.
  • Rugged high quality blend potentiometer with center click
  • Cermet trimming potentiometer (INPUT1) for input level matching
    - MX2 only
  • Screw input terminals with marking for signal-input (red) and GND (black)
  • Completely shielded and encapsulated - no shielding inside the
    instrument required.

After manufacture each unit undergoes a throughout test and inspection. This ensures each unit passes strict quality standards. Serial number is carried out for traceability purposes.

MX2 active mixer preamp


Technical Data:

  • Input Impedance: 2,2 MO,
    IN1, IN2
  • Output Impedance: 100 kO
  • Frequency Range: 5 Hz to
    110 kHz, -3dB
  • Supply Voltage: 9V to 18V
  • Current Consumptionr: 850µA
  • Blend Potentiometer with
    center click
  • MX2 only, Input 1: Level matching via trim pot.
  • Weight MX1 / MX2: 25g / 26g
  • Dimensions:
    L 20 x B 20 x H 24 mm
  • Reverse Polarity Protection
  • Input screw terminals
  • Output wiring: 150 mm
  • Power supply wiring: 150 mm