4-channel mixer, built-in reverberation effector, independent adjustment of reverberation parameters, built-in Bluetooth, digital display U disk player, with +48V phantom power supply, gain adjustment, treble adjustment, bass adjustment required by condenser microphones. "Features: 4 input channels, with +48V phantom power required for condenser microphones and insertion points for external signals: Each channel has gain adjustment, two-band equalizer, Distortion indication 1 pre-fader aux send and 1 post-fader effect send per channel 2-segment stereo level indicator, accurate signal level indication Built-in reverb effect, independent adjustment of reverb parameters Built-in U disk player with digital display Recording output interface, stereo balanced output interface High-performance monitoring headphone circuit, can be independent. Monitor each input channel, mixed output channel, effect channel Beautiful appearance and bright colors, suitable for all kinds of live performances and radio and television studiostechnical parameter: Maximum microphone input level: +16dBu Line maximum input level: +30dBu Maximum input level: 19dBm (1 KHz,THD=0.5%) SNR: 90dB Headphone output power: 100mW (1KHz, THD=0.5%, 200 Q) Equalization: Low Frequency: 80Hz±15 dB IF: 2.5 KHz±15dB High frequency: 12KHz ± 15 dB Gain Control: Mono: ・26dB, OdB Frequency Response: 20 Hz-20 KHz (+/-0.5dB) Total harmonic distortion + noise: ≤0.05% Power supply: AC12V