This is one of those plugins that you slap on a track and IMMEDIATELY notice the difference. It's basically a distorted saturation effect. I haven't tried it on synths, but if you put it in your drum tracks your drums GET UGLY. It allows you to turn your drums down and still have a good punch, while adding some dirt and grit. FAIR WARNING: you definitely want to turn the volume down before twiddling knobs (if it helps, the knobs have been pre-mapped in Ableton so you can click the triangle button and actually read what each control does) because some of the settings can distort things to the point of audio card/ear damage.