Some effects, like the Uni-vibe, are somewhat subtle to the ear. But that is certainly not the case with the MXR Blue Box. The Blue Box takes your input signal, adds fuzz and then generates a tone one octave below the original note. The result is a horrifying unique, almost synth-like sound which can be heard on such recordings as the guitar solo of Led Zeppelin's Fool In The Rain.

Box Dimensions: 2 3/8" x 4 3/8" x 1 15/16"

Controls: Output, Blend, On/Off switch, Input jack (1/4" mono), Output jack (1/4" mono)