Expression Pedal Setup & Calibration – Help Center

Connect a TRS expression pedal to the expression input on REACTOR Control to control Guitar Volume or Wah in real time.

Choosing What the Expression Pedal Controls

You can set the expression pedal behavior in the REACTOR App under Expression Control settings. Three options are available:

Auto (default) — The expression pedal automatically controls Wah when a Wah effect is active in your signal chain. When no Wah is active, it controls Guitar Volume instead.
Always Wah — The expression pedal always controls Wah, regardless of your current profile or signal chain.
Always Volume — The expression pedal always controls Guitar Volume, regardless of your current profile or signal chain.

Good to Know
- Your expression control setting is stored on the REACTOR Amp. If the REACTOR App is not connected, the pedal will use the last setting you saved.
- Performing a factory reset on the REACTOR Amp will return the expression control setting to Auto.

Expression Pedal Calibration

If your expression pedal does not respond accurately with REACTOR Control, calibrate it via the REACTOR app Settings menu or follow the steps below to calibrate it on your REACTOR amp:

Connect an expression pedal to the REACTOR Control. On the REACTOR amp, long press TAP + MOD buttons simultaneously (1 second) to enter calibration mode.
Top two FX LEDs (GATE, MOD) breathe white — push the pedal fully down (toe down), then short press TAP button to record. Top LEDs will flash white 3 times to confirm.
Bottom two FX LEDs (DRIVE, REVERB) breathe white — lift the pedal fully up (toe up), then short press TAP button to record. Bottom LEDs flash white 3 times and complete the calibration.

To cancel: Long press any FX button for 1+ seconds during calibration (LEDs flash red twice).
Timeout: Calibration exits automatically after 60 seconds of inactivity.