Alright, so I have a line 6 FM4 synth modeler, and i want to be able to use it with an expression pedal. For some reason, the Line 6 EX-1 expression pedals for these pedals have been scarce and expensive on ebay lately.

My question is, will the expression function on these pedals work with another expression pedal? If so, which ones? I know that volume pedals work as expression pedals for certain stompboxes as well.

Does somebody have any knowledge regarding this?