Tiny experimental expression pedal with 3 different modes of operation.




This device is the result of my desire to add as many features as possible in little space to optimize your pedalboard, with the added complexity of not wanting to use any other voltage than the one provided by the pedal expression CV voltage.


  • Button to momentarily set expression to minimum value (works in any of the 3 modes of operation).
  • Knob for expression/calibration.
  • 3.5mm minijack input for antenna or other possibilities (free minijack antenna is included).
  • 3-position switch to select mode of operation.
  • 1/4″ TRS expression out to pedal (cable not included)
  • No external power needed: Despite the internal circuit used is not passive, it uses the few voltage sent from the pedal to power Tripl3X.
  • Knob is made of CNC-machined aluminum. The rest of the body is 3D printed plastic.

Modes of operation (selected by switch):

  • Up position: Dragged expression.

    Changes expression slowly until it achieves the knob selected value. Best range to play is from 10% to 90% and it can take around 1-7s to arrive to the selected value, it depends on knob position and also the pedal used.
    Tip: When you find a good knob position, press the button for about 1s to repeat the dragging effect.

  • Middle position: Manual expression.

    Knob will change immediately expression value, exactly like the Expression Knob, no surprises.

  • Down position: Static electricity detector mode.

    Any object with static that gets close to the device will affect the expression value. Try to experiment with diffrent materials, rubbing objects with wool or anything. Be creative, experiment, use the minijack to convert anything into an antenna (sleeve pin will be used as antenna).
    Calibration: In this mode, knob is used to select detection threshold, start with knob at 100% and test with some charged object or try just with the hand. I get the best results between 90-100% with no antenna attached.


  • Works with any pedal with TRS (stereo) expression input. If you already have one of my devices Tripl3X will work in the same pedals too.
  • If your pedal is TS (mono) or TRS but sends CV voltages above +5V please contact me first.
  • If you have any doubts about compatibility just contact me and we’ll check together.

People in the US/Canada keep in mind:
– Shipping times are usually 4-6 weeks or even more.
– Despite sending with tracking number, USPS website doesn’t show the tracking information of packages from Spain.

Extended review by Guitar Pedal X:


Additional information

Weight 0,1 kg
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