Mixing consoles, mixing panels or consoles combine multiple audio signals into one or several main outputs, and usually include controls for adjusting the volume and tone of each individual channel.
Type of mixer
Mixers come in different shapes and sizes to suit a wide variety of work needs. They might be simple tabletop boxes for mixing a small number of sources; medium-sized control tables for live sound and small studios; or stand-alone consoles with up to 128 channels and integrated patch panels . Most mixers are analog, but in recent years digital mixers have become more and more popular - especially in live sound.
Typical panel layout
Mixing consoles usually consist of a series of identical channels and master control sections. Each channel is a vertical bar with controls (faders) that affect the sound from top to bottom.
Input: Each channel has an input jack, typically an XLR mic input or a "1/4" line input, usually with a selector switch for both. Most include a phantom power switch for powering condenser microphones.
Gain or Trim control: Depending on the type of input signal, the mic preamp or line level adjustment knob can boost or attenuate the signal to the appropriate level for the mixer. Fixed attenuation switches used to attenuate very strong signals are also common.
EQ section: To adjust the pitch and frequency of each signal, most mixers feature a variety of low-pass, filter, peak, and parametric EQ knobs. The frequency and bandwidth options for each band can be fixed or variable.
Sends and routing: Send knobs and/or routing buttons allow signals to be routed to different outputs or groups. Sends can be either pre-fader (for sending individual mixes to headphones or stage monitors) or post-fader (for submixing and sending relative amounts of signals to channel groups or effects devices, when the channel They will remain the same when the fader is moved).
Direct Outputs and Inserts: Additional jacks on the inputs are also common. Direct outputs allow post-EQ signals to be routed individually to multitrack recorders, while insert jacks include send and return on the same cable for easy repair in an external processor on a single channel.
Pan Control: On a stereo mixer, the Pan Control knob controls the amount of signal sent to the left and right channels of the main output, changing the perceived position of the sound. The default center position is to send equal signals to the left and right.
Fader: Usually in the form of a linear potentiometer, a fader can fine-tune the final volume of the signal sent to the main output. The default position is unity (no increase or decrease), increasing to +10db gain and logarithmically decreasing to 0db.
Mute and SOLO: The mute or off switch cuts off the channel for the main output, while the solo monitor switch mutes all other channels, allowing the engineer to temporarily hear a single channel alone. sound.
While each channel strip has the exact same controls, the master section has its own special setup functions:
Group Channels: A small group of mini channels that control the overall level of the group send (before being sent to the master fader). Groups are used to adjust submixes such as drum kits and backup singers.
Sends and Returns: The Master section also contains master controls for headphone, monitor, and effects send outputs, as well as effects returns for mixing in reverb or other external processor outputs.
Utilities: Some mixers also include a built-in talkback system for communication, a mono switch, a dimmer switch, or a "tape" output for recording stereo mixes.
Master Fade: Similar to the channel fader, the master fader controls the overall volume level sent to the master output.
