Two voices only mean double the fun with the Dirty Robot, a wild synth emulation pedal from DigiTech. The Dirty Robot serves up warm classic analog synth tones reminiscent of those from the ‘70s and ‘80s with one voice, and vocal formant synthesis for vocoder and talk box-like effects with the other. Using the Mix/Mod, Start/Stop, and Sens/Time knobs, you can change the frequency sweep, add in a dose of thick modulation, and change the Dirty Robot’s sensitivity — but it’s the 360 degree Drift knob that really lets you get crazy, allowing you to blend Square Wave with Sub and Octave sounds.