Hello? Ah, giant bug. My gosh. Studio Steve? Studio Steve? What are we doing
here? Why are we in the jungle? What does this have to do with compression?
You know what, I like that idea.
Yeah?
You know, I'd never realized before that you were so versatile.
Hello, Podskis. I'm Veronica, and this is the Pod Sound School. Today, we're going to
teach you all about compression, so by the end of this video, you will be able to understand
what compression is, how it works, and you will be able to put it to use on your podcast
mixes no matter what DAW you use.
Compression is the most used tool in audio production, and it's one of the key elements
to make your voice sound professional. So, today, I'm going to help Studio Steve teach
you all about compression, but before we get going, don't forget to hit the Subscribe button,
and if you haven't downloaded our free guide to jumpstart your podcast yet, go on the description
below, and click on the link, and join us on our Facebook group, Podcasting for Bosses.
Okay, let's get to it and out of this jungle.
Hey, everyone. Studio Steve here, and I hope you're ready to dive into compression. I'll
make this quick and informative for you. So, in order to demonstrate how basic compressors
work for you, I asked Veronica to read through one of her favorite Spanish poems from her
childhood. I asked her to be as dynamic as she could, meaning to fluctuate her volumes
from as low as a whisper to as loud as a yell. Audio compression is also referred to as dynamic
range compression. This is because it compresses the dynamic range and makes it less dynamic.
A simple way of saying what compression does is it makes what is louder quieter, and what
is quieter louder. Let's find out how compressor does this and how we adjust the settings.
We're going to use this basic compressor that comes with all of the pro tools versions because
it has a graphical display that helps us to visualize the components of a compressor,
and it also has an input and output meter and also this handy GR or gain reduction meter.
So, before we take a listen to Veronica's recordings and add compression to them, let's
learn what the components of a common compressor are. They our threshold, ratio, attack, release,
and gain. Gain is also commonly called output. Most compressors will also have a handy meter
that displays what is called gain reduction.
Okay, so let's get started with threshold. Threshold is a line we set on the volume spectrum
that tells the compressor how much of the audio to compress or apply gain reduction
to. Here, you can see as I adjust this orange knob that we see the line move from left to
right along this graph. The numbers along the bottom of the graph represent our volume
spectrum. Minus 60 dB is the quietest, essentially the silence, and the zero to the right here
is the loudest. So, when our audio coming through this track is barely at a whisper,
it will be much closer to the left side of this graph near the minus 60 dB. If we were
to set the threshold all the way up to minus 60 dB, we would be compressing the entire
spectrum of the audio. Likewise, if we were to set it to the minus zero dB, we wouldn't
be compressing anything at all.
Next, the ratio. Ratio tells the compressor how much gain reduction to apply based on
how many dBs crossed the threshold or the orange line. You'll notice that if I set the
ratio using the knob to a one-to-one ratio, the white line here becomes even corner to
corner. This signifies that there is not gain reduction being applied. As I raise this knob,
watch the shape of the white line change. You'll notice that the shape only changes
after the threshold, not before it. As I dragged the knob all the way to the right, the line
becomes completely horizontal.
So, what does this mean? Well, a common place to start with vocal compression is three-to-one
ratio. This means that for every three dB that the audio crosses the threshold, the
compressor will reduce its gain down to one dB. If the audio crosses the threshold by
six dB, then the compressor would reduce it to two dB or by a third. As the ratio gets
higher, so does the gain reduction. I like to think of it as how forgiving or hard or
soft the threshold is. If I set the ratio all the way to a hundred-to-one, that basically
means that no audio at all will be allowed to cross the threshold.
Okay. Moving on to attack and release. Adjusting the attack determines how fast this gain reduction
will take place. This is another way of determining how hard or forgiving our orange line or our
threshold is. You'll notice as I turn the knob from left to right, I get two different
units of measurement. One is ms or milliseconds, and to the left, we get this us abbreviation,
which is for microseconds. A microsecond is a thousandth of a millisecond, so they are
very fast. This means that if I turn this knob all the way to the left, the compressor,
we'll apply the gain reduction almost immediately, whereas, if I turn it all the way to the right,
it will apply it more gradually, and the threshold will seem more forgiving and natural.
The release component tells the compressor how long basically to hold onto the gain reduction.
The attack pushes down, and the release lets go. The release knob here actually kind of
works backwards from the attack knob. If I turn it all the way to the left, it will let
go very quick, and as a result, create a softer, more natural compression. If I turn it all
the way to the right, the milliseconds turns into seconds, and the compressor will be more
aggressive, and that threshold will seem much harder.
Lastly, we have a gain knob. Because we are reducing dBs or volume dependent on our settings.
The gain knob lets us make up for the reduction and to boost the whole signal, so we still
have a nice output happening on our track, which is also why it's called output. A good
way to adjust this is to monitor how many dBs of gain reduction you're averaging, and
then boost that many at the output. Okay, so let's pull up Veronica's recording and
see if we can make sense of how all this works.
You'll notice on her audio track, I have a compressor set up on the insert section, so
her voice will pass through this compressor before moving through the rest of the channel.
First, let's put the threshold at zero so that no compression will be applied and just
have a listen to her recording.
[foreign language 00:07:12]
Now, let's keep the ratio at three-to-one and the attack and the release where they
are. Let's play back her voice and start to adjust the threshold.
[foreign language 00:07:38]
This compression graph is cool because it gives us a moving red square that represents
her voice volume. As I lower the threshold, take a look at this meter here marked GR,
which stands for gain reduction. This shows us how much gain reduction is happening. Notice
what happens when I turn the threshold all the way down to minus 60 dB.
[foreign language 00:07:58]
As you can see, that's a whole lot of gain reduction, and take a look at the output meter
here. Our output level is now very low, so I'd have to adjust the gain knob here until
I get a decent output level.
[foreign language 00:08:13]
This is where we are making the what's quieter, louder. You will hardly ever see someone compress
a vocal this heavily, but this is a great demonstration of how compressors work especially
by processing it onto the wave form. So, let's look at the wave former for audio track. You
can see just looking at the wave form how dynamic it is. Let's copy the wave form onto
another track and process this heavy compression onto it to see what happens.
Notice how squeezed the audio has become. Even the areas of audio that were basically
silent like the room tone has now become very apparent. That is because we boosted the gain
so much, so now, let me show you a Studio Steve compression setting that I commonly
use on vocals that is a great place to start. You'll see the threshold is at minus 25, the
ratio is at three-to-one. The attack is 15 milliseconds. The release is 25 milliseconds,
and the gain is plus six dB. I'll apply these settings to Veronica's recording, and now,
let's look at the gain reduction.
[foreign language 00:09:18]
A good rule of thumb is to keep your gain reduction averaging around minus three to
minus four dBs of gain reduction.
[foreign language 00:09:25]
The big spikes or outbursts of your recording, they can have a gain reduction around eight
to 12 dBs, so starting from these basic vocal compression settings, we can now fine tune
the knobs to achieve a nice gain reduction and output level. Now, quickly before we finish
up, I want to pull up Adobe Audition and show you a compressor there. This compressor in
Adobe Audition is similar to what you will find in Audacity. You'll notice that there
are not any meters or a way to pass the audio through it as it plays similar to Audacity.
We would just have to adjust the settings. I have Veronica's same vocals track take on
here, and I'll just enter Studio Steve's vocal settings, and now, I know it will sound nice
for the mix. Okay, there you have it, Podskis. Hope this was useful.
There you go, Podskis. I hope you learned a lot in this video, and if you're still confused,
come and find us on social media at Pod Sound School, and come and join our Facebook group,
Podcasting for Bosses. We will love to answer any questions that you may have, so leave
them in the comments section below, and until then, happy casting. Oh, and don't forget
to subscribe.