Hi, actually it IS possible to use two effects at the same time. I had the same question. The answer is two get the two effects u want to use and set the effect positioning to parallel 3 (i think). This now(when in multi mode) will enable you to vairy what each instrument recives from channel c and b. Channel c and b sends can be controlled with the CHOR and REV levels in multi mode. *NOTE* You will not be able to hear the effects in performance mode when the effect is set to parrallel 3.
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