Einherjer represents the norse heroes it is named after: unrelenting and fierce. It is an overdrive with an active 3-band EQ, modifiable clipping setting, and a clean blend to reintroduce your clean sound. The blend control is meant for bass players who like to play through distortion. As a signal distorts, your low frequencies become high frequencies. This is why basses can't be run through most distortions; they lose their low end. Adding line level clean to your output reintroduces bass and makes the bass sound a lot more full.
Blend: Control goes from full wet (clockwise) to full dry (counter-clockwise).
Volume: Controls the volume of the wet signal before the blend control.
Gain: Controls the gain of the clipping section.
Low/High: High position cuts bass in the clipping section. Low position adds bass to the clipping section.
SI/MOS: Controls the clipping style of the OD. SI is for silicon diodes ans MOS is for diode connected MOSFETs. MOSFET mode yields higher output and less distortion while SI gives a traditional overdrive character.
Low: 40 - 100 Hz bandwidth at +/- 16dB
Mid: 650 Hz center bandwidth at +/- 16dB
High: 4K - 10K Hz bandwidth at +/- 16dB