You can set the EXP jack on Iridium to accept an expression pedal for real-time control over any one or more of the knobs on Iridium in any direction.
To set the EXP jack to Expression mode:
NOTE: EXP jack assignment persists through power cycles.
To assign knobs to be controlled with the expression pedal:
NOTE: Expression pedal assignment is saved independently per Favorite/MIDI preset.