i don't know if i'd want to use the tc di if i had a reddi. i'd just load up any effects in front of it and run it straight to foh. of course, that doesn't answer your question
i suppose you could get an xlr-1/4" transformer from radio shack and plug it into the tc's input. still, i wouldn't want anything acting negatively on the reddi's tone so i'm not seeing this as a particularly good idea. sorry...just being honest.