M81 BASS PREAMP DESCRIPTION • 3-Band EQ with sweepable midrange • Studio-quality Direct Out • Constant Headroom Technology™ for clean, crystal clear tone POWER The MXR Bass Preamp is powered by one 9-volt battery (remove bottom plate to install), a 9-volt AC adapter such as the Dunlop ECB003/ECB003E, a DC Brick™ power supply, or phantom power.
