Acoustic Amp Modeler/Direct Recording Preamp/DI Box Get that sought-after “unplugged” sound with practically no effort! Acquire natural warmth and presence as if you were running the signal through a tube preamp. There is an ultra-musical 3-band EQ with sweepable mids for accurate feedback control and eliminating the harsh harmonics of piezos. Super-high impedance lets you retain maximum signal integrity and dynamics. Use the ADI21 either for direct recording output with tube/microphone emulation or as a standard active direct injection box. The output is laid out on 1/4′ TS or balanced, gold-plated XLR connectors. A ground lift switch eliminates typical ground loop problems, and it runs on a 9 V battery or a DC power supply (not included).