The MXR M81 is a Bass preamp pedal that has a studio quality direct out in one small package. The M81 features a separate input and output level controls and a 3 band EQ section with a sweepable midrange from 250hz to 1kHz for maximum tonal flexibility. Itâs all delivered super clean with high headroom thanks to MXR's own Constant Headroom Technologyâ¢, and you can use the PRE/POST EQ switch to set whether or not your Direct Out signal is affected by the Bass Preampâs EQ section.