The Tech 21 SansAmp Bass Driver DI is a 3-channel, programmable rig-in-a-box similar to the TRI-A.C. for guitar, but made for bassists. The all-analog circuitry features drive, bass, treble, presence, blend, and level controls. Digital only in its programmability, you just tweak the knobs until you find a tone, double-tap on a footswitch, and it"s saved in that channel. Works great on stage or in the studio. Rugged all-metal construction. Operates via a 9V alkaline battery, phantom power, or the optional Tech 21 DC2 power supply. 7.25"L x 5"W x 2"H. 25 oz.3-channel, programmable rig-in-a-box Drive, bass, treble, presence, blend, and level controls All-metal construction Operates via a 9V alkaline battery, phantom power, or the optional Tech 21 DC2 power supply 7.25"L x 5"W x 2"H 25 oz.