Using a Voc Harmonizer in a live setting is a ART FORM in itself. Its tricky and you have to be very aware of what your doing if you want to make it sound authentic.On top of that your playing your instrument also at the same time. Knowing when to use it and how. I have seen acts with the most Horendous use of a harmonizer you can imagine. Use it right it will be a huge benefit to your act..... but use it wrong and you will make a fool out of yourself and to your audience.