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 of using an external adapter.Item type: Sound Mixing Consoleower: mobile power or USB Channel: 4bluetooth Connected: YesTotai Harmonic Distortion: 0.1%Frequency Response: 20Hz-20KHz/0.5dBS Ratio: 80dBMAX Outputs: 4V/MAXMIC Impedance: 2.4Mono Impedance: 11Stereo Impedance: 100Parametric EQ High: 12KHz/15dBParametric EQ Low: 80Hz/15dBsize: 15x18x5.5cmMaterial:ABScolour:blackPackage Contents:1 * audio mixer1 * USB wiring1 * Lotus lineOnly the above package content, other products are not included.Note: Light 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.