I second this, though I haven't tried the alternatives which I hear are also good. There is some value to specific kinds of pitch shifters, like the Boss Octav

I second this, though I haven't tried the alternatives which I hear are also good. There is some value to specific kinds of pitch shifters, like the Boss Octave pedal, the Digitech Whammy pedal, and Eventide's harmonizers. Depends on what you are trying to do and what kind of control you want.