Sweetsound Ultra Vibe speed controller pedal question

[abrackas]

I recently purchased one of these units that did not include the foot expression controller and was wondering if I could put any 1/4 volume pedal in there to change the speed with the sweep of the foot. Not sure where to look for a controller of this type (if a special cable is needed).

Thanks in advance and I will let you know how it compares to my Prescription Electronics Vibe Unit.