What is compression?
Compression is the process in which we strive to reduce the dynamics between the loudest and quietest parts of an audio track. In turn we are boosting the quieter signals and reducing the louder tracks. Compressing Vocals seems to be something most beginners have problems with.
In this tutorial compression will be used on vocals, however compression should be used on most of your tracks production, to ensure that we have complete volume control of the entire mix.
Should I Always Compress My Vocal?
As mentioned above, Compression is used to subtly manipulate tracks to make them sound much more natural and easy to understand without impacting the quality, making it exponentially easier to listen to. Compressors tend to bring much more color to tracks. In short, ALWAYS compress your vocals. The following steps that I provide in this blog are the most important components used when it comes to compressing vocals. I will leave out some of the less important parameters as this guide is more so geared towards beginners and what exactly you need to start with to have great compression on your tracks.
Common controls every compressor has
At the end of the day it absolutely depends on which compressor you’re using but most of them do have the same parameters used to determine the action that the compressor takes on your vocals. Below I will explain the basic functions that most compressors share. Your compressor may have some different functions and/or titles to each of these controls, but most will have the same capabilities. Understanding the basic functions is vital to using any compressor so I suggest beginning with a stock compression plugin.
Sure, there are some compressors that are much easier to use, even some that will take two stock compressors to achieve their sound, but in the end all compressors have the same capabilities if you use them correctly. The difference is simply how precise one compressor is over the other and how well the AI is built to analyze the audio for you, automating the process. Below I will break down some of the common controls that every compressor has.
When manipulating the threshold we are changing the level in which the compression interacts with our vocals. The vocal will only be compressed once it reaches the level of threshold selected. If I were to set a threshold of -8dB and my vocal begins to spike up to the -8dB level, then the compression would begin so that it does not surpass that level. For the remaining time, compression will not be engaged with the vocal. Threshold is arguably the most important element of compression so it’s vital that you take your time learning how to actually determine what threshold is right for your vocals. Each microphone/recording environment is different, causing a difference in volume in recording. Be sure to consider the volume levels for each and every vocal that you mix individually.
Attack will dictate how quickly vocals are compressed once they reach the threshold level that we have set. The Faster the attack, the faster our vocals will be engaged by our compressor. If our Attack Time is too high we may start to experience some natural distortion within that vocal. Fast attack is typically used on a vocal that has many more syllables as the cadence of that vocal is on the faster side.
Contrary to attack, we have a release time as well. This will dictate the time it takes for the vocal to return to the original sound after it is compressed. Typically a release time will be much higher than an attack time. A high release would most likely be used on a track in which the artist is singing and holding their words out much longer than a rap vocalist would.
1.) Applying Threshold
Upon compressing vocals the first question we must ask: “Is the vocal consistent?” Typically vocals tend to lack volume control as it is natural for us to talk/sing louder at certain points than others. This is where a compressor can give us that equality that we’re looking for. Keep in mind, some parts of your track may be higher energy in which you might have been much louder than the verse before that. It is quite normal for us to have dynamic in the volumes in which we sing or rap.
As you can see, the figure above shows the difference between uncompressed and compressed audio. Find the low points and determine how loud they are. You can then add a threshold capping the volume off at that point. This will help build consistency and allow us to hear every single work within the recording. Notice how the compressed audio has much less dynamic and seems to have much more volume control than the uncompressed audio.
Depending on what kind of compressor you have you will now be able to see that the vocals are now ducking underneath the threshold that you set. See the figure below. (I’m using a Waves Compressor.) You can compare these lines ducking as the tops of mountains being cut off to make all of the mountains a consistent height.
2.) Applying Attack/Release
To put attack in simple terms - A fast rap verse would require a faster attack as it has many more syllables than a slower singing verse. Our goal is to make every single word audible as we use a fast attack to bring about more clarity.
In contrast to attack, you can imagine what we’d do with our release. The slower the words are coming out, the higher release we’d use as we do not have to be too concerned with the attack.
In a song that has a medium speed we’d simply just go half and half on our attack and release. At the end of the day, it truly depends on the vocals that you’re mixing in particular. Never use the same Attack and Release on just any vocal.
3.) Ratio & Gain
The next question we have to ask ourselves: Do we want our mix to sit on top of the mix or inside of the mix? What will determine our next course of action will be Ratio + Gain. Ratio can be described as how much of the compression is being held, the higher the ratio, the stronger the compression.
With most rap vocals for I’d want a higher ratio so because my vocals are going to be a bit less dynamic. Rap vocals are more based on the cadence and flow more so than the dynamics. When it comes to a singer and/or a live event you will want the least amount of compression necessary to make it sound a bit more natural as the dynamics are what keeps listeners entertained. With rap vocals my rule of thumb is keeping the ratio around 5.0:1 but this will be situational of course.
As we begin to manipulate our gain dial we will be able to essentially move our vocal behind the mix, inside of the mix, or above the mix. There’s no real rule of thumb when it comes to where your gain should be, it is entirely the situation and what you believe sounds best for the specific track. Most listeners tend to stay in tune with vocals that sit perfectly within the mix. As you continue to compress you will begin to get a better ear for what sounds best for said track. Be sure to play around with the Ratio & Gain back and forth until you reach the intended sound.
Want to save some time? Imagine if you could have a means to apply my exact process automatically, without manually compressing vocals every time… Well, that’s actually possible! With my vocal presets you can decide on a genre and vibe for the vocals that you’re mixing and apply it instantly. With my vocal presets I strive to save artists time and money by automating the vocal mixing game! Check out my packages below:
At the end of the day compression may sound incredibly simple to most but the truth is after 5+ years of audio engineering I am still learning about compression every single day. As you invest in new compressors and mix different vocals on a regular basis you will come to find that compression is very dynamic in a sense of the experience you’ll have when working on a new project. If you’re new to compression please remember that these are the three tips that we want to refer to every time we are compressing.
In order to fully understand compression it is vital that you engrain the fact that compression is about consistency into your head. When is the vocal too loud? Where are the inconsistencies? We must determine these questions and apply our compression with precision.
Our two most vital plugins are EQ and Compression, if you master these two plugins everything else literally just becomes ear candy. If you want to learn more about EQ check our my blog on Mixing Vocals From Scratch.
(Below is a video that goes much more in depth on compression and how I apply it to my mixes.)