Compact preamp/direct box for electric bass guitar that is based on the respected OBP-3 preamp and features fully sweepable midrange frequencies in addition to bass and treble controls. It also features proprietary Adaptive Gain Shaping circuitry (AGS) to provide the unit with ultimate tone shaping flexibility. It allows the player to kick in an additional gain structure and EQ with the ''stomp'' of a button. 18 volt operation gives the unit plenty of headroom to reproduce the most dynamic playing style. Separate Gain and Master controls allow user to dial in just the right gain structure for any instrument. Other features include cut and boost of treble, mid and bass frequencies, an unbalanced output that can drive a power amp and four switches – Ground Lift switch, Pre/post DI switch, Engage switch and AGS switch. The unit can be powered by two nine volt batteries, phantom power or optional universal power supply.