The Black Eye by EarthQuaker Devices is a clean MOSFET-based boost that will provide you with an insane 30dB boost with minimal tone coloration. Use the Black Eye as an attenuator by rolling the knob down past noon for versatility, or use it as a buffer after your effects chain. Though it doesn't create any kind of distortion or overdrive on its own, you can use it to push your amp or favorite pedal into an impressive, overdriven sustain.