New to the world of music production? Here’s a valuable tool in your arsenal to get acquainted with: audio compression. It might appear difficult to understand at first, as learning its role in enhancing your mix can be somewhat challenging. But in this article, we’ll delve into the power of the mighty compressor, including what it is, how it works, and how it can be used in the mixing and mastering process to help you achieve the perfect sound in Studio.

What is compression in music – An overview 

Let’s say you’re trying to shape a lead vocal for your track. At times, your vocals overpower the mix; but in other instances, it fades into the background, obscuring vital lyrics and phrases. 

This is when you reach for audio compression. This handy tool restricts the dynamic range of the vocal, reining in the unruly dynamics of your mix and making those overly-loud vocals quieter. The result is a vocal that sits comfortably within the mix. 

Fun fact: compressors, like many other audio devices, have their origins in military applications. They were initially developed for the purpose of transmitting crucial orders behind enemy lines. In these situations, the clarity of the message was paramount, as any loss of signal could lead to misunderstandings or misinterpretations. To ensure the fidelity of electronic messages over phone lines and radio waves, electrical engineers invented compressors.

Over time, compressors transitioned into the commercial market, primarily finding their place in the radio broadcasting industry of yesteryears. They underwent significant refinement, with specialized controls added to tailor the compression effect to the specific demands of the broadcast field.

How do compressors work? 

Having explored the concept of “What is compression in music?”, we can now deconstruct the compressor’s functions to aid your understanding of its functionality.

1. Dynamic range control

The main purpose of a compressor is to narrow the dynamic range of an audio signal. Dynamic range essentially measures the difference between the loudest and quietest parts of a track. Compressors work by making the loudest sections of the audio quieter, resulting in a more even and manageable volume throughout the track. 

2. The controls at a glance

Here are the common controls you’ll see on compressors.

  • Threshold: The audio level at which the compressor will begin to work.

  • Ratio: The ratio determines how much the compressor reduces the audio level once it crosses the threshold. For instance, if you choose a ratio of 2:1, the compressor will permit 1 dB of signal to rise above the threshold for every 2 dB it detects. If you opt for a higher ratio, like 10:1, it means the compressor allows 1 dB of signal to surpass the threshold for every 10 dB it senses. The impact becomes more pronounced with higher ratio values.

  • Attack and release: Attack specifies how swiftly the compressor reaches full effect once it detects signal above the threshold. Release determines how quickly the compressor disengages when the signal falls below the threshold. Adjusting the attack and release settings enables you to shape a track’s groove, introduce distortion, create a sense of space, blend multiple tracks together, and more.

  • Makeup gain: This control dictates how much to boost the overall volume after applying compression. It’s essential to note that makeup gain is not merely a post-compression volume knob. It ensures consistency and loudness throughout the audio.

It might seem counterintuitive because compressors are designed to reduce loud sounds. However, by making the louder parts quieter, you free up more headroom in your mix, allowing you to elevate the overall volume effectively. In essence, compressors become indispensable tools for making everything louder.

What does compression sound like?

To gain a deeper understanding of what is compression in music production, let’s compare a drum track created in BandLab before and after compression:

Here’s what happens if I use a compressor on the drum track:

The compressed version sounds more balanced and consistent in volume. The result is a steady sound. But this is just one way to use compression. Remember those attack and release times? We can use them to shape the groove of the sound:

The attack time is longer, allowing the transient to pass through before the compressor clamps down. This effectively changes the way the hit feels. 

How to use compressors

Now that you know what audio compression is, let’s talk about how to use it. Here are some tips to help you get started:

1. Start with low ratios

As it’s easy to abuse compressors and suffocate your music, you’ll want to begin with low ratios. Start with 2:1 or so, until you can hear the effect of compression on your audio. 

2. Let the threshold be your guide

Rather than getting too caught up in adjusting the ratio control, focus on the threshold to gauge the compressor’s impact when determining your settings. This approach enhances the audibility of the effect.

When you’re in the process of fine-tuning your compressor – as opposed to just exploring its impact – seek that ideal threshold sweet spot. If it’s set too high, you won’t effectively compress anything. Conversely, if it’s set too low, it’ll impact everything, making it challenging to optimize the behavior of the attack and release controls in your favor.

3. Explore attack and release

When it comes to shaping your sound, the choices you make with attack and release settings can work wonders. For instance, employing a slow attack combined with a fast release on drum tracks can yield a punchy and aggressive sound. Be careful, though, because an excessively fast release can introduce unwanted gritty distortion.

Conversely, a swifter attack time will suppress the initial transients in a sound, so it’s important to keep this in mind. Pushing the attack too far into the speed zone, however, might bring about undesirable distortion.

In general, when striving for a smoother sound profile rather than a punchy and aggressive one, opt for a medium attack coupled with a slow release. This combination helps in achieving a more balanced and polished audio outcome.

Where to find compressors in BandLab

With an understanding of what is compression in music production, you can begin utilizing them in BandLab to improve your mixes. Here’s a guide to locating your compressors.

  1. Select the track where you wish to apply compression, and click on the FX button.

  2. At the bottom of your screen, a window will appear. Look for a plus sign with the label Add Effect beneath it, and click on it to access your effects.

  3. Navigate to the Dynamics section within the ensuing menu to find a list of compressors. Be aware that each of them sound different – and that’s a good thing! 
what is audio compression bandlab

For the purposes of getting to know your compressor, the DIGI Comp is your workhorse. It is the most versatile of the options in BandLab. It even has an extra control called “knee,” which smooths the compressor’s behavior around the ratio point.

Another dependable option is the FBK Compressor. This one emulates the behavior of renowned processors found on numerous chart-topping records, offering all the controls we discussed earlier. It’s an excellent tool to grasp the interplay of threshold, ratio, attack, and release settings.

Picture these aforementioned compressors as training wheels on a bicycle, aiding you in mastering the basics before you venture into more advanced techniques.

Other compressors like the BL 1176 and the TECLAB BA-2A, are modeled after vintage classics. They possess their own innate character profiles and might require a bit more exploration to fully understand. Think of these processors as BMX bikes – you’ll want to establish a solid foundation before attempting any advanced maneuvers.

You’ll also note other processors like DeEsser, Compander, GTR Squeeze, and Noise Gate. These modules are much more specialized. Their usage is outside the scope of this article.

Make your own compression presets

Here’s an advanced tip for you: Seasoned professionals often view certain compressors not just as dynamic control units but as color enhancers. This is because different compressors infuse a unique character into the sound. In fact, experienced mixing engineers frequently explore predefined settings on their compressors and cycle through them before fine-tuning by ear.

This practice isn’t about taking shortcuts; it’s a testament to the understanding that with colorful compressors, the settings themselves possess distinctive inherent characteristics.

To show you what I mean, I’ve made a preset in BandLab with the BL 1176 compressor:

I’ve named it the 76 ABI Starting Point, with ABI standing for All Buttons In – a classic feature of 76-style compressors. In the following example, I’m going to use this preset on four different sound sources: two acoustic drum kits, one 808 beat, and a synth bass. All of them are played at different tempos. 

Note how each loop in this example has a similar distorted character. This character relies on the interaction of all the settings. Move any knob, and the character will begin to change. If I know I want to maintain this character, I have it on hand as a preset, which saves time and keeps the creative juices flowing. 

We often time our compressors to fit our material. But for these colorful compressors, it’s often good to start with a preset starting point.

Common mistakes in audio compression  

While compression can be a powerful tool for music producers, it’s surprisingly easy to stumble into pitfalls. Here are some common missteps:

1. Over-compressing

It’s easy to get carried away with compression, especially when you’re trying to even out the levels of a track. But using too much compression can result in a squashed and lifeless sound. It can also fatigue the listener’s ear. So, it’s better to use the least amount of compression that will suffice.

2. Mismanaged attack/release settings

The settings for attack and release on a compressor are pivotal for molding the effect. Music producers who are new to the game often struggle to grasp their operation and may inadvertently work against their intentions. Always remember that the attack and release settings are your fine-tuning tools, and their precision is critical.

3. Using compression when there is absolutely no need

When confronted with unfamiliar tools, you might feel inclined to slap them on everything to test their impact. While this is fine for practice, such wanton abandon can be harmful for your actual productions. Not every element requires compression. For example, electric guitars are already compressed because of how an amplifier functions. So, remember to employ compression judiciously, and only when you need it.

With a fundamental grasp of what is compression in music, you’re ready to incorporate audio compression techniques into your music production. Head straight into Studio to enhance your upcoming tracks and creative projects!