You can trigger it via footswitch (there are 3 such inputs: ON\OFF, Program A, Program B). You can also trigger it via MIDI, as program changes in a MIDI sequence or by playing chords on your keyboard. The most basic way to trigger it is by selecting a preset Style and just singing into it (has XLR and Line inputs and outputs).
This unit can generate up to 10 parts (if desired): the original vocal plus 4 harmony parts x 2. Each part includes adjustable real-time pitch correction, random delay, and formant control (gender: male or female voice). The onboard digital mixer allows volume and pan control of each part. It is a 19" rack-mount unit.
Michael