Whether you call it a mixing board, mixing console, sound board, or audio mixer, its main purpose is to change the levels, timber, and dynamics of audio signals in order to combine them.
Musicians aren’t the only people who use mixing boards. You’ll find them at radio stations, television and film productions, and public addresses like political rallies or college commencement speeches.
In its simplest description, a mixing board allows the whole band to play through the same amplified speaker
system. The mikes for the drum set, guitar amps, and vocals are all processed through the mixing board. In some situations, the keyboard and bass also run directly into the mixing board. From the mixing board, the sound is sent to
monitors to allow band members to hear themselves and also to speakers for the audience to listen.
There are all sorts of mixing boards—some are digital and some are analog. An analog mixer is commonly thought to be easier to use than the newer digital mixers. Analog mixers feature one knob, fader, and switch per function. Digital
mixers are more versatile and offer more features like special effects.
Regardless of what kind of mixing board you purchase, the controls can usually be divided into three sections: channel
inputs, master controls, and audio level metering. The channel inputs are where you plug in various instruments, mikes, and amps. Master controls set overall volume level and audio level metering monitors volume for individual items.
Channel Inputs
In general, each instrument or mike gets its own channel. Depending on the specific mixing board, the channel is either stereo or mono. Each channel usually has an XLR input, RCA input, and quarter-inch jack. These inputs are to plug in mikes, guitar amps, drum kit mikes, keyboards, and bass guitars.
Trim Knobs: One of the first knobs in each channel is the trim knob. This knob sets the threshold for volume output on each track. For example, if trim is set to the middle, the fader can go from +15db to -10db. If you turn the trim up, the fader can go from +15db to -45db.
Input Volume Faders: These faders navigate between the threshold designated by the trim knob settings. If you keep a volume fader at the bottom, the output will be silence. Moving it up increases the volume set by the threshold of the trim knob.
Pan: The pan knob allows you to adjust the amount of sound coming from the left and right channels. Probably one of the easiest knobs to use, you simply turn it to the left to send more sound to the left side of the channel, or turn it right to keep more sound in the right channel.
Equalizer Knobs: One of the purest ways to adjust the depth and richness of the track is through manipulating its highs and lows. Most mixing boards have separate knobs to adjust the highs, lows, and mids.
Solo and Mute: These buttons are often grouped together. The solo button turns everything off except the soloed track. This allows you to hear one track or instrument at a time. Mute does the opposite, turning off a selected track.
Master Controls
The main output controls are generally found on the right-hand side of the mixer. Large consoles sometimes have these controls in the center. You’ll find controls for master volume, talkback control to communicate with musicians through headphones or monitors, and local headphone controls.
Main Volume Faders: The primary function of the main volume fader is to limit the maximum left and right volume of the mixer. The fader allows youto change the volume range of the speaker or headphone knobs. These knobs set the maximum volume the main volume fader can move to.
Meters: The meters, usually LEDs, show how much signal is getting to the mixer and how much is leaving. Most modern mixing boards use peak program meters (PPM) to accurately monitor levels.
