The MXR M81 Bass Preamp Pedal brings studio‐quality bass tones to any performance or recording situation with its innovative Constant Headroom Technology. This compact Phase 90‐sized pedal features separate input and output level controls that maintain crystal‐clear signal integrity at volumes that would cause other preamps to distort. The versatile direct output can be switched pre or post the comprehensive 3‐band EQ section, allowing you to dial in the perfect tone for your amplifier while sending an optimised signal to the PA system.
The pedal’s 3‐band EQ section includes a sweepable midrange control spanning 250Hz to 1kHz, providing extensive tonal flexibility for any bass guitar or amplifier combination. Built‐in features include switchable buffered bypass/true bypass modes, a ground lift switch to eliminate hum issues, and multiple power options including 9V battery, standard power supplies, or phantom power from your mixer. Internal switches allow players to disable the direct output and buffered bypass for true bypass operation when only using the standard output.
Since Dunlop Manufacturing introduced MXR pedals in 1972, they have established themselves as pioneers in guitar effects, winning multiple awards with their Bass Innovations line and creating modern classics like the Carbon Copy delay pedal. The M81 represents the perfect solution for adding a new voice to passive basses, enhancing any amplifier’s tone, or providing that special touch for particular songs while maintaining the pristine signal quality that MXR is renowned for.