The Matrix Mixer

It’s a fair bet that every single Q-SYS design is going to use at least one Matrix Mixer at some point.

It’s your go-to tool for mixing audio channels together.

It may seem simple, but it has a lot of properties and controls so let’s just make sure we understand everything this versatile component can actually do.

Look in the Mixers folder of the Schematic Elements Library, and drag a Matrix Mixer into your design.

By default it starts with eight mono inputs and eight mono outputs.

Let’s wire some sources and destinations just so we have something to play with

I’ll add a mono Audio Player and a Q-SYS network microphone as inputs,

and we’ll send our outputs to a Q-SYS network soundbar and a network amplifier with some wall-mount loudspeakers.

If we open the Matrix Mixer’s control panel, we’ll see where it gets its name:

there’s a matrix—or grid—of crosspoint knobs that allow you to customize how much of each input is mixed to each output.

And because this is a matrix mixer, we’re gonna fill this video with all kinds of cringe-worthy references to that 90’s Keanu Reeves movie . . .

Much Ado About Nothing, which is just a great Shakespearean romantic movie about a bunch of mix-ups. You should watch it, it’s great.

Back to the mixer, this control panel is laid out similarly to a live production mixer.

Each input is represented by a vertical channel strip.

As far as order-of-operations for your gain goes, your first step would be to adjust the trim knob at the top,

if you need to globally adjust the incoming audio up or down a little bit to make sure it’s entering the mixer at healthy, nominal level.

These default at 0dB, meaning that by default no change is made to the incoming audio.

Next you would use the channel faders at the bottom to mix the gain levels of your inputs to your preference.

This is also a global change, and is generally the control most people will use for making gain changes.

There are also bump buttons if you prefer to use these on a UCI rather than sliding a fader . . .

and don’t overlook the labels at the bottom where you can identify each channel.

. In the real world, this is done with a roll of tape and a marker.

You’ll notice that Label Controls are on by default, so only turn those off if you’re insane, completely unorganized, or just feeling really lucky.

And there are other common mixer controls here, like Solo and Mute,

so you can globally mute an input and then remark to yourself,

“Silence is the perfectest herald of joy, Ha ha ha.”

That’s a . . . that’s a Much Ado quote, as I’m sure you know.

So, the next step is to adjust the crosspoint knobs in the matrix section.

This is where you decide how much of each input you want to mix to each output.

By default these are all set to -100dB,

which means that no audio is passing through the mixer at all.

This is done intentionally as a safe way to make sure you make the choice of where each input goes.

If I want the Audio Player to be sent to the soundbar at the same level I set down here on the channel faders,

I would set its crosspoint knob for Output 1 to 0dB.

That means I’m making 0dB of change from the fader level.

But if I want the Audio Player to be a little quieter in the wall-mount loudspeakers,

I might set the crosspoint knob for Output 2 to -10dB.

Now if I adjust the main fader later it will affect the volume in both of these outputs,

but output 2 will always be 10dB lower than the setting of the fader.

All of these changes can be made in Emulation Mode, but until you’re actually in the room, these are probably just going to be guesses for now.

You’ll want to come back and finesse them once the system is up and running.

Once you’ve made your mixing decisions, there’s one last gain-staging step, which is in the output channel strips.

Here you can adjust the total mix for each output up and down, rather than adjusting each of the crosspoint knobs individually.

Don’t forget you should also name your outputs using the labels on the left.

Let’s jump back to its properties now and see how you can change this matrix.

First off, you can customize the number of inputs and outputs. There’s no need to have more channels than you’re actually using.

Also, please take note of the difference between mono channels and stereo channels.

If my Audio Player were a stereo audio player, I wouldn’t want to wire it to two mono inputs,

because then I’d have to mix the left and right channels independently, which would be fairly annoying.

Instead I’ll add a stereo input.

The pins may look the same, but if you hover your mouse over them they’ll note which ones are mono channels and which are stereo.

The stereo input pairs will always appear after all the mono input channels.

So those left and right-channels can now be controlled by a single channel strip, which just makes more sense.

If you need really granular control of each output mix, you could engage Crosspoint Mute Controls,

Crosspoint Solo Controls, and even add “Pan Per Crosspoint” controls to pan each input left and right for a stereo output.

Now rather than globally muting a channel, I could mute just input 3 for output 2,

“Oh, I wonder that you will still be talking, Signior Benedick, nobody marks you. Haha!”

But adding all these crosspoint controls does start to make this control panel a bit unwieldy, so I’d only suggest enabling these if you really need them.

Next, let’s look at Control Banking, which determines how many controls are on screen at once.

Let’s say I set my Input Bank Size to 16 channels, but I have 17 total input channels.

The control panel will only show the first 16, and you’ll have to navigate to the second Bank in order to find your 17th channel strip.

You can customize the number of channels to your preference, for both inputs and outputs.

Using control banking can make it easier to keep track of your channels in large mixers, rather than forcing yourself to scroll through an extremely large control panel.

There are a couple of other controls that are inspired from a physical mixing console, like the Cue bus.

Adding a Cue bus will add a new cue output pin, and you can mix any of your inputs to that Cue bus using the Send button.

By default this is sent Pre-Fader Level, meaning it ignores the gain change you’ve made on the channel strip fader,

but you can choose to send them AFL—or After Fader Level—instead.

You could also enable any number of VCAs. If you’re not familiar with a VCA,

it’s basically a way to group certain channels together so that you can adjust all of their gains by the same amount with a single fader,

which shows up to the right of your normal fader strips.

As I said, a lot of these features are inspired by a physical mixing console … but the matrix mixer is honestly most commonly used for simple mixing and routing.

Whether you have a handful of inputs that need to be mixed together to go to a number of outputs,

or whether you’re just summing a stereo channel down to a mono channel, you’ll find that the Matrix Mixer is absolutely mandatory in pretty much every design.

If you want to dig deeper be sure to check out its entry in the Help file …

but there is one last feature I want to demonstrate right now, which is the 2-D Panner.

The 2-D Panner is actually a completely different style of mixing.

This only works if all of your inputs and outputs are mono, for reasons you’ll understand in a moment.

When all your channels are mono, you get a property called “2-D Matrix Panner” which you can set to Yes.

In this mode, your matrix of crosspoint knobs is replaced with a spatial map,

and the gain of each input that is mixed to an output is based on the proximity of their channel icons.

For instance, if I drag input 1 close to output 1,

(“Oh, Hello Beatrice . . . I do love nothing in the world so well as you, is that not strange?”)

you can see a sphere of influence that increases, meaning input 1 is fully present in the output 1 channel.

If I start to move it, you’ll see its gain decreased in output 1 and increases as I move it towards other outputs.

If you think of this as a birds-eye view of your venue, you could literally move a sound around the room like an object.

Thus the name, 2-D Panner.

Normally panning is only in one-dimension: left to right.

Two dimensions lets you pan it left and right, as well as forward and backward.

This is a very similar method to the way modern cinemas provide immersive audio experiences.

Each input now has a radius control, which changes how close it has to be to an output icon to be mixed there,

A large radius would give a gentler sense of movement,

whereas a small radius would let you pinpoint individual outputs

There are a lot of creative applications for the 2-D Panner for high-impact immersive installations

like high-end corporate lobbies, theme parks, museums, any interactive space.

If you want to go the extra mile you could automate your inputs to move around the room using custom scripting, or even a clever use of snapshots and control logic.

The 2-D Panner may not be the most common mode of using the Matrix Mixer, but we just wanted to make sure you saw that it exists before we leave this mixer behind.

We’ll take a look at the other mixers available in the next video.

So let’s take a break, and I bid you a fond adieu until next we meet.