TANKS! Unity Tutorial - Phase 8 of 8 - Audio Mixing

Phase 8 - Audio

With the GameManager selected

we're going to put in some music

for our game, so we need an audio source.

So select the GameManager game object,

Add Component, type in 'sou'

hit return and you'll have yourself an audio component.

Then if we click on the circle select

and choose BackgroundMusic as the clip.

Then finally check Loop

So choose the BackgroundMusic clip,

check Loop at the bottom.

I'm just going to keep saving my scene to update it.

We're going to create what's called and audio mixer.

In Unity we have audio sources,

they output all of the sound, they might be on

game objects in the scene, they might be on instantiated objects.

But basically they all need to route in to a mixer

in order to balance them with one another.

So select the AudioMixers

folder in the project.

Click the Create button and choose Audio Mixer.

So this is a Create button on the project window.

Choose Audio Mixer.

I'm just going to rename this MainMix.

Then I'm going to go to

Window - Audio Mixer

So it's control8 on pc, command8 on mac.

And I'm just going to grab this and

dock it somewhere sensible, I like to do it

next to the game view,

I just find that useful, but you might want to

do it during the game so it might make sense to

dock it by the scene view, it's totally up to you.

The idea is that we want to

route each audio source that we've made

during the day in to a particular,

what we call group.

If you've used audio software before you might call these

tracks or channels depending on which package

you use, but Unity calls them groups.

So each group of sounds needs

it's own group. Makes sense?

So our master is where all of those

groups will end up, so what you'll see

if you look at the mixer

Is that we have things on the side

with + buttons, so Groups is one of those.

So if I click on this + button

I can make a new group.

The first thing that I'm going to do is make

a group for my music

Then each time I make a new group

I need to reselect the master because I want

each of those groups to be a child of that.

So I reselect my master,

I hit +, and the next group

I want to make is for the sound effects,

so I just call it SFX.

And then finally we need one

more for our driving audio.

So the idling and the engine sounds.

Remember I'm making these

and reselecting the master each time

so that they're children of that.

So now we need to go through all of our

audio sources and route them in to the

correct group that we've just made.

Then we'll actually do the balancing

but first we need to hook everything up.

So the first thing I'm going to do is select

my Tank prefab, so I go to my

Prefabs folder and I select Tank.

And this should become second nature once we've done

a couple of them but the first thing I'm going to do

is to look at the audio sources there.

So if I zoom in a little bit for you, what you'll see

under each audio clip, the second

parameter there is Output, and that is

which group this is going in to.

So the first audio source we know is for driving,

so I'm going to click on the circle select

and you'll see MainMix and you'll see

CompleteMainMix which is used for the complete game,

so ignore that, look at the MainMix

and we're going to select Driving.

So Engine - Sounds in the first

audio source will go to there,

remember the second audio source was for

sound effects so under Output

we'll choose SFX.

So one more time, the first audio source

should be routed to Driving, the second to SFX.

And that's our Tank setup.

Then the next thing that had an audio source

was our Shell.

and if you expand the Shell you'll see the

ShellExplosion which has the audio source attached to it.

So in the prefab, in the project, just click

the arrow next to it to see the child object ShellExplosion

and then you'll be able to route that also

to the SFX mixer group.

So what else needs routing?

Well we just added our GameManager

and we just put on BackgroundMusic

so we need to set that up as well.

So for that audio source I'm just

going to click the Output

and set that to Music.

So the TankExplosion also has

to be routed as well so in the Prefabs,

TankExplosion prefab,

the audio source there needs setting to sound effects.

The SFX mixer group.

Okay, so now we're ready to mix,

everything is hooked up in to that so I'm just going to show you

really quickly, please don't do this, I'm just going to demonstrate.

So what you'll see in the mixer

is that all of these levels

are moving around and when I actually do something,

the SFX gets a level too.

But nothing is balanced yet, so we're going to do

that but we're also going to use an effect

to make sure that the sound effects can cut

through everything else.

So the Music group, I'm going to set the attenuation,

and by that I simply mean the level,

of the music down a little bit.

It's kind of loud, it's compressed as you'd expect.

I'm going to bring that down to -12, so do that now.

Drag that fader down to -12.

Then I'm going to select the Driving group

and set that way down to -25.

So it's super loud and super obnoxious sounding

and we don't really want that, we'll drag it all the way down

so that it's nice and subtle in the mix.

-25.

Then for the Music we want

the music to be ducked down every time

there's an explosion, so we want the music

level to dip every time a sound effect comes in.

So we do that with something called ducking.

So ducking basically means that you can

use 1 source to decrease

the attenuation of another.

At the bottom of the Music group

I'm going to click on Add.

So here I can add a Duck Volume effect.

And when I do that you should see it on the inspector,

I get this effect, so when you select

any of these groups, so you can see I can click on

them and they highlight in blue.

When I select Music I've just added Duck Volume,

And it says it's first thing is

a warning saying 'No Send source is connected.

There's basically no other group

sending a signal to this group in order to

tell it to duck, so we need to sort that out.

So what I'm going to do is go to my SFX group.

My SFX, I will select it,

and then at the bottom of SFX

I'm going to add a send.

And that send has a receive.

So you need to just basically send the signal of this

to something and the only thing

that we've got is this Duck Volume effect

on the Music group.

So I'm just going to select that

and then how much of this do we want to send?

Well we want to send the entire level

So instead of nothing, -80 decibels,

we're going to drag it all the way to the top.

So we're not going to add this or reroute the signal,

we're just using it to command

that effect, so drag it all the way to the right

I.E. full.

What does Duck Volume mean?

Duck Volume is basically

using one signal to subtract from another.

What you'll see in a moment is that we have

a certain threshold for how much signal

is going to be required to decrease that.

Okay, so I'm going to reselect my Music.

And I'm going to look at that Duck Volume.

What you'll see is that we have a

meter here effectively, so I'm just going to

show you how that works.

So when I play the game

this Duck Volume is waiting for something to be played

from the sound effects, so if I fire something

you see that this yellow comes up

from the left to the right.

But there's a white line

which is representing the threshold

So what I'm going to do is reduce the threshold

so that it starts to

pull down the volume of the music

out of a particular amount of signal coming in

from the SFX group.

so I'm going to pull that threshold down to

round about -45.

So now I'm just going to turn this up

so you can hear what I'm doing.

Now when I actually play it

You can hear the music gets pulled down as that

threshold comes in.

Then what I'm also going to do is change

a couple of other settings there,

I'm going to change my Ratio to 250%,

so it's going to curb it even further,

and my Attack Time to 0.

So as soon as there's any signal at all

that's passing that threshold it's going to come

in to effect.

The attack time is usually how long it waits to

come to full effect, but we don't want it

to wait, we want it to start straight away.

So Attack Time should be 0.

Ratio should be 250. So now.

It's nice and prompt. As soon as I start hitting

the music goes down.

So it's going to be hard for you guys to hear on these speakers

and obviously you can check it out with headphones as well.

But that's exactly what's happening.

So it's time for you to save your scene,

and play it one more time,

because we have completed our training day.