I've owned a few pedals that work best with passive signals - no buffer or preamp in front. Unfortunately you often want those effects downstream of some other effects and they either don't work correctly or don't sound right. In my search for how to modify an effect to work better with an active/buffer signal I found this webpage: Guitar Pickups Simulation It describes a seemingly small, passive (non-powered) circuit you could build into a small enclosure, or even install within an existing pedal enclosure, to provide the effect an emulated pickup load. Theoretically you could string whatever you want in front and use this circuit to provide your Ultra Fuzz, Mammoth, Fuzz Face, Oxfuzz Germanium, etc. etc. a passive pickup load so it sounds it's best. Has anyone had any experience with this type of thing? Is there an existing off-the-shelf pedal based on this idea that you can already purchase?