The S7303 four-channel audio mixer includes a built-in sound processor, microphone, and stereo line inputs for pro-audio applications. The mixer is configured with a built-in USB interface and audio level control faders on the output and all input channels. The mixer is also configured with gain, high, mid, low, PAN, AUX, and EFF control knobs on all channels. Each channel includes a peak LED indicator. The high-accuracy level meter allows users to monitor the sound signal levels. A built-in phantom power with a LED indicator and control button can be used to power condenser microphones.