The Mixing Console

Signal flow is an important concept in recording and it is no different when understanding a mixing console. Even if you have to imagine and invisible signal that you can trace over your mixer will put you ahead of the game. The input strip of a mixing console is where signal begins and once you understand how one channel works you can sit behind any console confidently. An input strip is just a preamp that boosts incoming mic and line level inputs to a signal that can be worked with by your mixer and outboard gear. Just remember, signal flows from the top of the input channel down to the faders.

 

The first dial in an input channel is the gain trim or just gain or trim. It's important to know that depending on manufacturer or design there can be different names for things labeled on a console but believe me when I say, they all do the exact same thing. Gain boosts the low level signal of a microphone to an optimum level that can be processed and mixed. Gain can be tricky to get perfect because too much gain will cause clipping in your audio and too low will introduce noise into the recording. A good way to start finding gain levels is rehearsing the loudest part of a performance and setting the gain level just before the signal is about to clip and setting faders to zero.

 

Once signal has been adjusted with the gain knob signal ends up at the auxiliary sends. Auxiliary sends is an area that allows you to move signal to outboard effects, microphone mixes, output sends or even to a speaker in your bathroom. While signal moves top to bottom on an input strip auxiliary sends signal moves horizontally across all the input channels that are using the same auxiliary send. An example of using auxiliary sends would be turning the auxiliary 1 on both channel 1 and channel 2 and sending the signal from channel 1 and channel 2 too a reverb unit.

 

Now that signal has moved from gain to auxiliary sends it will end up at the EQ. Depending on manufacturer or model a mixing console can have a variety of EQ styles. Generally you can find four continually variable overlapping frequency band controls each having its own bandwidth and ability to cut/boost frequencies +/- 18db. A great tool to use with EQ is the in/out button which allows you to switch the EQ in or out (bypass). I've said this before but if you record with EQ or any effect it is difficult to revers during the mixing stage afterward if you change your mind about the effects.

 

Signal continues on finally to the pan knob, fader and bus outputs. The pan knob moves the input signal anywhere in the stereo spectrum moving signal between left and right speakers and any percentage in between. The fader adjusts the sound level of the input signal that has moved through all the parts of the input channel. During recording keeping your faders at zero is a good place to start if you feel things are too loud or too quiet try adjusting the gain knob first then slide faders. The bus outputs allow you to combine several input channel signals into one channel for easy manipulation. For example, taking the five microphones that are on the drum kit and moving them to a bus you can adjust the volume of all five microphones with one fader, now turning up the drum kit is easy.