Chorusing effects are produced by slightly delaying an input signal and reintroducing it against the original while simultaneously varying the pitch by a small amount. This combination of signals gives the effect of two instruments playing at once - a chorus of instruments, so to speak. Unfortunately, many chorus pedals have the tendency to cut low end, leaving a thin, clinical tone that harkens back to the days of 1980's overproduced excess.
MC-3 MICRO CHORUS page at Guyatone 's website...