X - analog multiplier, VCA and ring modulator - minijack version

4-quadrant multiplier

The X module is a versatile 4-quadrant multiplier, usable as ring modulator, VCA, waveshaper and much more.
The two input voltages 'X in' and 'Y in' are multiplied together, providing the multiplication product voltage 'W out' (internally attenuated to keep the signal within the working range).
If audio signals are being used for both inputs, the result will be a ring modulation. If a CV is applied on one input and an audio signal on the other one, the CV will control the amplitude of the audio signal (like a VCA) or will invert it. If CVs are applied on both inputs, one CV will modulate the amplitude and polarity of the other one.
'4-quadrant' means that negative modulation voltages can be processed too. The result is an inversion of the modulated signal.
Input 'X in' is equipped with additional control functions:
The knobs 'Level' for adjusting the input amplitude (amplification max *3) and 'Offset' to add an offset (DC) voltage in the range from ca. -5V to +5V to the input signal (whereby a 'dry/wet' control for the 'Y in' or a zero-point shift of the 'X in' can be achieved).
Furthermore, the switches 'inv' for inversion of the 'X in' input and 'lin/exp' for a exponential conversion (hereby the X is working in 2-quadrant mode, meaning that only positive voltages from X in will be processed, which is adequate to rectifying behaviour). The 'exp' modus suits well for loudness-correct VCA applications.
Further, the input 'X in' is equipped with a red LED for indicating an eventual overdrive.
The 2nd input 'Y in' is intentionally made without any additional control elements, to keep the complexity of the module as low as possible.

• Width: 6 HP (30,2 x 128,5 mm)
• Depth: 35 mm
• Processes both audio and CV signals
• Ring or amplitude modulation
• Voltage controlled amplification
• Exponential conversion
• Wave shaping
• Dynamic expansion
• 1 input with adjustable offset and level control, polarity changer and exponential/linear switch
• LED for 'X in' limit indication
• Easy to use
• Power consumption (+12V) : ca 25 mA