Pitch Shift / Detuners
Detuners are similar to pitch shifters, but the intervals between the detuned signal and the original signal are much smaller, usually expressed in cents (hundreds of a semitone). Most effect processors use percentages of semitones to express the shifted notes' distance from the original. For example, with a maximum of 50%, the pitch is exactly one semitone (50 cents) up from the original.
Pitch shifters allow you to create multiple voices from a single note input. This is usually governed by the shift parameter and can be spread over 4 octaves.
Parameters
Speed - This controls the effect's stereo imaging. The higher the setting, the wider the image. The lower the setting, the more monophonic the effect becomes.
Balance - Adjust the left/right positioning of the dry signal in the stereo sound field.
Detune Parameters - These units tend to have a range of detuning controls which will produce a knock-on effect throughout. The 4 octaves, could be split amount 6 group for example. If the first octave is adjusted to a high level, the remaining octaves will then be affected. Not all of these have to be used.
Key - Depending on the sophistication of the unit, the key can be chosen for the pitch shifting harmonies to reside in.
Scale - Depending on the tonality of the music being played, different scales can be chosen (major, minor, dorian, lydian etc)
Interval - The interval between the resultant harmonies.