When you are Monitoring it sends audio inputs that are going happening on the board/application to a separate sound sources such as monitor wedges, front of the house, stage sound and headphones. The key to a good monitor mix is isolation of parts and being able to hear your self when creating those parts. Hearing your self correctly allows you to preform or meet your expectation of the tracks easier. When working with bands or live broadcasting be prepared to have multiple mixes for your AUX out puts or bussing outputs. People require to hear different input tracks or parts at different volumes and the mix is tailored for different but specific purposes. Below description explains the following terms:

AUX/Buss: An “Aux Send” is output used on live sound, audio software and recording mixers. It allows you to create an “auxiliary” or alternative mix in which you have an individual level control over each independent input channel on your mixer to your “Aux Send” output.  The aux output audio work independently from the main mix output and give you the ability to route multiple input channels to a single output while leaving out the channels you don’t want to hear. When mixing monitors for bands you want to work left to right for inputs on the board to position on stage.

Types of AUX/BUSS


PreFader buss means you're sending the input audio at the very beginning of the input channel before the fader. Pre-fader sends are normally used for monitors, cue mixes, or headphone mixes. Engineers usually use PreFader so moves made with the faders in the front of house won't effect the stage volume.


PostFader means you're sending the input audio at the end of the fader input channel with all effects applied to
the aux send. This is typically used for front house to carry the same audio across the board to your groups, reverbs, and effects.

Audio Output Routing FOH:
When setting up and mixing large audio systems you will send each section to separate aux signals in post fader. You can assign the type of out put you would like it be for the aux send. For example, it can be mono, stereo, stereo L, stereo R, mid and so on. Looking left to right you see line arrays flown to the left and to the right. XLRs run out the left and right to a speaker that is daisy chained to the rest of the speakers. On the master fader you can control the left and right speakers. Some engineer include the subs in the chain with a cross fade from low end to high end. Crossfade ensures that certain frequencies won't come out undesired speakers. For example, you do not want high end 1,000hz - 20,000hz coming through your subs that take up 0hz-800hz frequencies spectrum and you don't want your low end of 0hz to 800 to go to your high end speaker outputs (line aray).

A common practice is putting subs on their own aux output in mono. This allows you to have low end control and the ability to drive low end on a single fader. So for example, you have your Main L+R , AUX 1(post fader) output as your subs, AUX 2(post fader) as your center fill, and AUX 3(post fader) as your line aray speakers 100 yards away.

You have your main mix control through your master fader for L+R speakers above. Once you level your inputs for your main outputs leveled you need to send those input levels through AUX 1 to activate the sub. This gives you free control of each individual track and how much level you of each individual track you would like to send to AUX 1 (subs). When input send levels are balanced you can ride the AUX 1 fader to add or take away volume going to the sub to desired liking. If we send individual input levels to AUX 2 we will hear sound going to our center fill and have control of how much sound would like to go to the center by adjust AUX 2 fader. Fills are used to add sound where sound is lacking. If your L+R is 50-100 yards away from each other, there will be a dead spot in the middle because theres no speaker sending sound. Fills are used In primarily large concerts to cover a large areas or venues that need sound in multiple rooms. Now say you are covering 500 yards in front, the FOH system can only push sound so far so AUX 3 will be our far fill. We can send each independent input levels out to AUX 3 to activate our far fill. When there are great distances between speakers you will need to time delay to adjust phase. With modern technology you can adjust phase of speakers using an RTA mic and SMART for phase correction/eq with white noise. Most live boards feature a time delay on output channels. 

This is just an example of how outputs are configured by the audio engineer. You can configure your ins and outs any way to tailor to specific show environment/requirements. There is no specific way to assign them but there is logical methods to assign inputs and out puts by working left to right on stage and the mixing board/project.

Compresor/Limiter On Monitors

Apply a light compressor on AUX from .5 to 2 ratio of compression to help control peaks. Apply a limiter at the end of the AUX output to protect against accidental SPL overloads that can blow your monitor speakers. This is a great way to protect your speaker gear.

Checkout the Compressor/Limiter article to learn about there functions.