I had some problems with it, it's on warranty repair, I'll see when I get it back if the problems are solved (clicks and other weird stuff happened, like a short circuit inside the module...). but he sound is very good, not a self-oscilliant filter, more of a smooth one, very good for drums I think, and/or to filter the sounds coming from external mics or radio music module. For a synth voice I always prefer a 24db ;)