We can't connect the expression/Wah pedal through MIDI interface. But it will be very convenient to add an analog expression/Wah pedal in front of the guitar input. Lots of guitarists are using this way on the stage and it works even better than digital Expression/Wah in MIDI interface. As you know, the MIDI parameters only can support 128 level dividing but analog expression/Wah is continual control.
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