EarthQuaker Devices Tone Job EQ & BoostThe Tone Job is a complete tone enhancement tool designed around a stereo preamp to cover as much frequency range as possible. What does this mean for you, the user? It means it can handle a wide variety of frequencies from electrical guitars, bass guitar, synthesizer machines and just about anything else you can plug in. The treble, bass and middle controls will cut or boost up to 20db. In addition to that, the level control will boost the signal