I have the QTron+, but I assume this would work for the other models, minus some features. I put it on Low Pass (LP), direction "up" (versus down for Dancing in the Street), response time to fast (although slow could work too), range to Low, and then I put the Peak at noon, and then it just boils down to the sensitivity setting, which I set at a level which makes the overload LED blink when I strum hard.
Hope that helps,
Zach