wusu Bass guitar DI box instrument sensor DI box PRO D2 impedance converter D2 BOX ProDI is used for acoustic guitars and bass guitars. *ProD2 is used for stereo keyboards and drum machines Connect consumer audio products with professional audio equipment Eliminate the "clicking" and "humming" sounds caused by the grounding loop. Outstanding features Super-strong design, prolongs service life Plug-and-play, easy to operate Fully passive design, no need for power supply