If you change the value of that pot lower then the volume pedal may not work correctly, as most of the volume pedal arrangements use it like a shunt, which brand model do you have as i have two of mine traced and may be able to give you a concrete answer (it's a simple circuit, but i don't remember off hand how's it's hooked up at the moment ). Generally the main pot's value is selected to give you the response you want (like high or low impedance), and the minimum volume's pot is selected to enable a full mute all the way up to no effect (volume at 10 ) ... generally it has no effect tonally ... it's simply that the math must balance out ... so to speak ... for it to work correctly.:33: