Input Processing

We’re ready to start making actual adjustments to the audio in our system.

We’ll start with Adjusting the Input Settings, then move on to the Output settings.

These Setup Wizard shortcuts will take you to the Master Inputs and Output screens,

and now we’ll explore all these other pages for each input and output channel.

We’ll show you where to find your PEQ, Dynamics and Gate controls,

so you know how to make adjustments when you want to make them.

If you’e interested in the finer details of these adjustments,

we’ll have deeper dive videos for that.

Let’s start with properly gain-staging your signal.

The objective of gain-staging is simple –

– you’re matching the input sensitivity of the mixer to the output level of the source.

Start by playing one of your source devices—or if you’re using a microphone, talk into it.

Whichever one you do,

make sure the signal level from the source gets as loud as it is ever likely to be in use.

On the setup screen, you’ll want to adjust the Input trim

until the loudest peaks are into the yellow range but nothing is clipping into red.

We highly recommend using the MP-M Cue function to aid in this.

Just like a professional mixing console,

the MP-M Cue function lets you plug in headphones or earbuds

and listen to input and output signals without effecting the sound in the zones at all.

You can do this in the equipment room, far away from the active zones—

—just engage the Cue button for each source and use the Cue Level button to adjust your headphone volume.

Once it’s done, remove that input from your Cue and move on to the next input.

If your system includes video sources,

you might also be using a video switch that introduces a little bit of latency to your video signal.

When this happens,

the lip movements of the announcers on screen appear to be out of time with the audio you’re hearing.

This is sometimes called “lip flap”.

The solution is to delay the audio signal using the Video Sync Delay.

Typically the delay created by a video switch is only a frame or two:

so if your video is 24 frames per second then each frame is 41.6 milliseconds,

so you may want to start in the 40 millisecond range when adding Video Sync Delay.

Start there to see if you can get the lips and the sound to match.

If your video is 30 frames per second each frame is 33.3 milliseconds

so you should try around 30 milliseconds to correct this.

Don’t forget to enable this delay if you’re using it.

Now that we’ve truly finished with the Setup page, let’s look at the other configuration pages.

The PEQ gives us access to a 4-band parametric equalizer,

and you can select the gain, frequency, and width—or Q—of each adjustment.

You can also move the handles directly on the graph.

If you don’t have as much experience with this,

you may wish to engage Simple mode, which will limit your control to the gain knob only.

If you’ve already made some adjustments before you engage Simple—

—don’t worry, it keeps your previous settings exactly where they were.

On the Dynamics page,

you’ll see options for engaging either a Compressor or an Automatic Gain Control (or AGC) on this channel.

In order to activate either one you’ll need to toggle the “In” switch,

and you’ll notice that any channel with its Dynamics engaged

will have an indicator illuminate next to its fader on the channel strip.

This also illuminates the graph on screen, to help you know when the processing is active.

For a Compressor,

you can once again engage Simple Mode if you’d like to simplify the control here to a single knob,

or you can fine-tune the threshold, attack and release time, ratio and gain of the compression.

For the Automatic Gain Control,

this would often be applied to music tracks that might vary in average volume.

You want to turn down the songs that were recorded a little louder,

or turn up the songs that were recorded a little quieter.

Some good values to start with would be to set the Max Target to -3dB,

and the Min Target to -15dB giving you a 12 dB window.

The way the AGC works is that it applies gain or gain reduction

to try and get the RMS (average) signal level inside the window.

If the RMS value is above, the AGC will reduce gain,

and if the signal is below, it will add gain up to the Max gain value that you set.

If you reduce this window size,

you make the AGC circuit work harder trying to keep the signal in the target window

and those changes might be too noticeable.

The Max gain is the most gain that will be applied while trying to push a low level signal into the window.

The Threshold is the point at which the circuit no longer looks at the RMS –

– this means that for long fades or gaps in songs

it will no longer push the gain up to try and get the song louder (and bring up the noise floor).

The Release is how long the circuit waits before it stops applying gain or gain reduction –

– the longer the number the slower the circuit

and with an AGC you generally want it to be slow so you don’t hear the gain changing.

Finally, the Gate.

Similar to the Dynamics,

you’ll notice that engaging the Gate will illuminate an indicator by the channel strip.

You can fine-tune all the settings of how you’d like this channel to be gated open or closed,

or you can engage Simple mode to just make one general gating adjustment.

You might also notice that you can assign channels to be controlled by our Auto-Mixer,

which can regulate the levels and share the gain of multiple microphones.

This feature works great for panel discussions where multiple talkers have open microphones

and you don’t necessarily want to be riding their faders.

We’ll discuss this in greater detail in our video that covers the Mixer section,

so let’s ignore this for our initial setup.

Once we’re happy with our Input settings,

we can check that task off of our Setup Wizard, and move on to the Outputs.

In the next video we’ll look at our Output settings.

Move on whenever you’re ready.