1.The mixer is equipped with, input gain and high and low bass adjustment, the built-in 48V phantom power supply is suitable for direct power supply of condenser microphones, high-definition headset output port, MP3 player, bluetooth receiver, and a connected PC sound card.     2.The mixer is small and light, and can be directly connected to the USB port of the PC for power supply. No additional power supply is required. It can be operated by connecting the computer to the power supply through the USB, eliminating the trouble of using an external adapter.     Item type: Sound Mixing Console     ower: mobile power or USB AC / DC     Channel: 4     bluetooth Connected: Yes     Totai Harmonic Distortion: 0.1%     Frequency Response: 20Hz-20KHz/±0.5dB     S/N Ratio: 80dB     MAX Outputs: 4V/MAX     MIC Impedance: 2.4     Mono Impedance: 11     Stereo Impedance: 100     Parametric EQ High: 12KHz/15dB     Parametric EQ Low: 80Hz/±15dB     size: 15x18x5.5cm     Material:ABS     colour:black     Package Contents:     1 * o mixer     1 * USB wiring     1 * Lotus line     Only the above package content, other products are not included.     Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.