Question Despite selecting the desired key with the left-hand knob, the hardtune effect is really out-of-tune on my C1 pedal. Answer This is almost certainly due to the knob needing to be re-calibrated. If it is out of calibration you may unintentionally be selecting D# instead of D, for example. To re-calibrate the knobs, please refer to this FAQ: /articles/FAQ/VoiceTone-Singles-Pot-re-calibration-228160827