STEREO 4 IN 1 OUTThis portable audio mixer mixes four sound inputs into one stereo output. Each potentiometer controls the volume of each channel independently, and the volume does not affect each other. Easy to carry and operate. EASY TO ADJUSTThis stereo line mixer splitter has standard switch gear. With bass and treble controls, you can adjust settings to your needs and easily drive a variety of headphones and external amplifiers, can be output by headphones and speakers. WIDE COMPATIBILITYThis headphone mixer with 3.5mm stereo jack, can directly drive headphones or connect power amplifier. The input interface is compatible with PC, mobile phone, laptop, etc. Output interface is compatible with speakers, headphones, bar speaker, etc. SAFE TO USEThe working power of the sound mixer board is DC 5V12V DC5.5 x 2.1, and the magnification is about 2 times. The quiescent current is about 8mA. Using NJM3414 low voltage and high current, the maximum driving current is 70mA.