Analog circuitry with constant headroom technology
Input control for adjusting the signal strength at the input of the pedal
Output knob for adjusting the pedal volume
Active 3-band EQ with selectable center frequency for the mid control
Balanced XLR Direct-Out with pre/post switch and ground lift
Bypass footswitch
Internal DIP switches for setting different bypass options for the Direct-Out and jack output
Compact metal chassis
Powered by 9V battery or optional AC adapter
The MXR M81 Bass Preamp in the official video:
Compact Preamp for E-Bass with flexible EQ and Direct-Out
The MXR M81 Bass preamp comes in a handy pedal format and turns out to be a secret weapon for studio and stage with its flexible and top-class sound.
Analog circuitry with Constant Headroom technology
Thanks to the analog circuit with Constant Headroom Technology, the MXR M81 delivers a crystal-clear Bass sound without distortion or unwanted noise. The input control determines the signal strength at the input of the circuit, so that even powerful active basses can be used with M81 Preamp without any problems.
3-band EQ with semi-parametric mids
For precise tweaking of the Bass sound, MXR's M81 BassPreamp features an active 3-band equalizer that boosts or cuts bass and treble up to 18 dB. The center frequency of the midband can also be tuned between 250 Hz and 1 kHz to define the character of the Bass sound.
Direct Out
In addition to the classic jack output, the MXR M81 BassPreamp naturally features a balanced XLR Direct Out, which can be used to feed the Bass sound directly into a mixing console or audio interface. The Pre/Post switch determines whether the processed preamp signal is output or the pure input signal.
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