+48V Phantom Power For the reliable power source, the stage/studio sound mixing console features a +48V phantom power supply. has ultra-low noise design Three Band Equalizer 4 channel Audio mixer with 3 band equalizer, which allows tone control and precise high quality sound over High/Mid/Low USB 2.0 Compatibility Can connect to a USB stick to play & record audio. Can connect to PC, Smartphone with compatible adapter, Cannot use bluetooth at the same time Reverb Knobs 2 Independent reverb knobs, You can control the reverb according to different occasions, this incredibly versatile mixer will make your vocals even better. Professional DJ 4 Channel Sound Mixer This DJ controller 4 channel audio mixer with Dual Mic machine by Tiimge is the perfect way to mix audio from MP3, mic, and bluetooth connected devices. 1-2 channel has gain control, Treble/Mid/Bass/Control, FX Reverb control & independent volume control. 3-4 Channel are RCA stereo inputs, this channel only has volume control, For input and connection computer music, vcd, dvd, cd player. USB 2.0 Audio Interface, for Computer Playing & RecordingBuilt-in FX Reverb Effect, 1 & 2 Channel FX Reverb Independent knob & 3-band EQCombo Jacks (XLR+6.35mm) for MIC/LINE Inputs3.5mm AUX Input Jack for Phone Playing MusicRCA Jacks for Stereo Input and Output, 2-TK RCA Input Jacks, 6.35mm Main Output Jacks3.5mm Jacks for Microphone Input & Earphone Monitor OutputIncompatible: speakers whose interface is optical or coaxial The professional 4-channel audio mixer is dual-handheld, with complete functions, light and convenient, and strong practicability. easy to deal with various occasions. DC 5V Power Supply, Please use a 5V 2A power plug The built-in DSP chip performs intelligent processing on audio, effectively reducing audio noise, improving sound quality and beautifying audio. Question Answer Q：Why the mixer cannot read the USB stick / USB stick not working？ A：Please check if the music in the USB stick is in MP3 format A：Please check if the USB stick has the numerous software program/folder A：Please check whether the power supply is normal. Occasionally, the power supply of the USB interface of the computer is insufficient, which will cause the mixer to be unable to read the U disk & the wireless microphone that comes with the mixer cannot be used. You can try to use a 5V 2A power plug to supply power. Recommend: USB stick only stores music in MP3 format Reminder: MP3 function cannot be used at the same time when using Bluetooth connection