Join Maxim Jago for an in-depth discussion in this video Applying compression to voices, part of EPK Editing Workflows 04: Audio Cleanup and Special Effects.
Compression is an almost magical tool for improving the richness and the punch, if you like, of vocals. It's a little bit like adding a, a little s curve to visuals when you want to increase the depth, the sense of three dimensionality of your media, when you're working with visuals. And it's very simple to use. But I must admit, when I first starting working with compression I had a real mental block about it, because it doesn't actually compress anything.
It actually makes things louder. I'm going to apply a compression effect here to our audio track that has Carmen's voice on it. We've got several clips here and because our multi-track session is nicely organized, any effects I apply to this track are only going to apply In this case two sections of her voice. With the effects rack in track mode, all I have to do is choose the first option on the list and go the amplitude and compression, and I'm going to choose one of several different compresses here.
I'm going to go for the multi-band compressor. There is a dedicated speech compressor there as well. Here we go with the speech volume leveler. But I find the results from the multi-band compressor are a little bit more subtle and pleasing. So I'm just going to select that in the effects rack and hit Delete. As is so often the case with new features, I think the multi-band compressor does look a little bit like an overwhelming wall of buttons and options, but it's important, as usual, to simplify the view by looking for those dividers.
So here at the top, we have a graph that indicates amplitude over frequency. So, on the right, here's the overall amplitude and along the bottom edge we've got frequency. And you can see these white lines separating out the bands. In fact those bands represent areas controlled by these four slider controls, or in fact, these groups of controls. There are four of these, and there are four bands within the frequency graph. Now I'm going to pull back to an earlier part of the timeline so we can hear Common's voice, and I'm going to press Play with the spacebar.
>> Or my soul mates, we come from the stars, and. >> So, right now we're getting pretty much default audio level. I'm going to switch this to something really obvious that will just really add some punch to her voice. I'm going to choose pop master. And this is going to preselect some options for us that's going to really bring up the level a little bit. Have a listen to this. >> It's, were, are my soul mates, you know, we come from the stars. >> Now, what I want you to notice is the red marks that are turning up at the tops of these meters.
What's happening here is, the compressor is raising the level for the audio within each of these bands. Let's imagine we're just talking about one band for now. Let's take this middle range which has the one kilohertz range, goes from, well, let's have a look. We're going from about, there it is. 127 hertz up to 2000 hertz, so within this band, this orange region, we're lifting the level. We are increasing the amplitude of the audio, but we are also limiting the maximum peak level.
So at the same time as increasing the volume we're capping that volume. The result is that the audio never becomes so loud that it overrides, that it blows out the recording medium, instead we've just got it at a pretty consistent top level. But the quieter parts of the audio are none the less louder, so the net effect is that the quiet and medium amplitudes sections become fairly loud and the parts that were already loud just don't get any louder.
This is compression. You're making it seem like it's louder, and there is more energy in it, but the peaks stay about the same. So we've got a number of different options here. I can see this to, goodness, Enhance Lows. Doesn't do too much for us. I can choose Classical. We come from the stars and, eventually in the lyrics. >> Softens it out a little bit. I'm going to leave this on Pop Master, but I'm going to pull down the output game. This is an overall adjustment to our level because I'm aiming really to peak somewhere a little over minus 60B, and if I play back now you can see,.
>> M mate or, or my soul mate you know, we come from the stars, and eventually on the lyrics you know, I. >> There we go I need to pull it down a little bit but that's just fine. So you also notice that we have a hard limiter which really just caps the amplitude. But I want it to have a little bit of a natural flow and natural adjustment. You can, of course, go in here and set the limiting threshold anywhere you want. Each of these are not just information, they are controls. You've got how quickly the adjustments applied. How quickly the adjustment is released.
How much the compression is over the certain threshold, and even a gain control. If you play with these in your own time, you'll quickly work out what they do. But all I need is to make sure that this is applied to my track, and here it is. And now every piece of audio with Carmen's voice on this track is effected by it. >> On earth. Well he's chasing me because he's running out of energy, shooting it because. >> So it just adds a little bit more punch. Now, at the top of the multi-track display, we have four buttons that define the modes for these track headers.
And at the moment we're on the inputs and outputs, which doesn't do all that much for us, it gives us an overall track level control. And if we were using hardware with multiple audio channels, we could specify the inputs and the outputs with this. What I'm interested in right now is the second option, the effects mode. And if I just resize this track a little bit and maybe pull out the size of the headers, you should see something quite familiar. This is showing me the multi-band compressor. In fact this is literally the one over here in the effects rack.
So, if I turn this off, you see it updates, turn it on, it updates. If I choose a different track, I see the effects for that track, which of course, in this case are none and if I choose this track I get the effects displayed for it. So this is actually a duplication of the interface. And I suppose it's just another way for you to access the controls. Now when I was first shown this, I thought it seemed like a bit of a waste of time but actually, it's pretty handy. It's nice having a bigger effects rack to work with when you're doing more complex layer-combined effects, but most of the time you're going to put one or two on a track and you just might as well do that in the track header.
In any case, that's an introduction to compression, which is really great for filling out vocals.
- What can be fixed in post?
- Assessing audio
- Getting audio into Adobe Audition
- Sharing audio between applications
- Reducing noise
- Adjusting audio levels over time
- Using audio effects creatively