What input meters? The unit is not clipping. I set the in/out switches to line when used in FX loop, but it sounds more or less the same no matter how I put them. It sounds as bad in the loop of a JCM2000 as a Mesa Rectifier.
The only way I can make it sound decent is to split my guitar signal, running one straight into amp A, and the second signal through the PF into amp B. What I've found since my last post, is that it responds better when I use the neck pickup. That leads me to believe that if I cut certain high frequencies, I could make it sound good. I'll get hold of an EQ to experiment. Maybe a noise gate in front of it would be beneficial also?