The Pyle Pro PMX462 3-Channel Audio Mixer with Built-In FX and USB Interface is versatile and easy to use, and features a clearly labeled set of controls. The Gain controls on Channels 1, 2, and 3 are used to adjust the input gain level for individual devices connected to these channels. Likewise, the individual Level controls for these channels adjust the output level for that corresponding input channel. The Main level fader is a master control for the overall mix. The optimum settings for a clean sound will vary depending on the particular devices that are connected to the input channels. Each individual channel has its own red Peak LED indicator light next to the channel's Level control knob to show when the level for that channel is very high. Additionally, the 5-stage LED Level indicator panel provide a more detailed view with green, yellow, and red LEDs. For cleaner sounds, you will want to keep the levels within the green and yellow indicators and avoid peaking, where the indicators becoming red.