A Simple Guide To Compression

A Simple Guide To Compression

A Simple Guide To Compression

In music production, compression can sometimes cause confusion for budding music producers, as it can seem quite complicated regarding what exactly it is and how to use it effectively.

What Is Compression?

Much like EQ, compression is another important tool in music production. Compression can be one of those areas of production that can take a little while to fully understand but put simply it's a form of dynamic or volume control. 

A lot of people believe that compression is about making things louder, but it is in fact the opposite. Compression 'squashes' the loudest parts of the track you're working on to make the dynamic range more level. For example, if one part of a vocal recording is sung quietly and the next part gets a lot louder, the quiet part may be hard to hear in the mix whilst the louder part is too loud. This can be levelled out with a compressor. The trick is not to over compress it but to level it out whilst still retaining some dynamics.

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When To Use Compression:

There are lots of uses for compression, including taming peaks in recordings, sidechaining as well as some more creative uses. In this blog we'll be focusing on compression in its more basic use, to avoid making this simple guide more complicated.

One thing I want to mention is that you don't need to use compression on every single track in your mix! You have to let your ears be the judge and go from there. A good place to start is to critically listen to your track and see if you can hear any drastic or obvious volume changes within the individual tracks. The example I mentioned earlier about the quiet and loud vocals is quite a common one but can occur in any track where there is quite a lot of dynamic movement.

Features Of A Compressor and Terminology:

Here is a list of the terminology of compressors and how they work together.

Threshold:

Put simply, the threshold is the volume at which the compressor turns down the signal. If the threshold is at 0 then no compression will occur and if you adjust it slightly it will start to compress the loudest parts of the track. The more you adjust it the more squashed the track will become, and you'll lose more dynamics.

Ratio:

The ratio works in conjunction with the threshold, to determine how much gain reduction occurs when the signal goes above the threshold. It's called a ratio and is expressed as a ratio (e.g.: 4:1) as it's comparing the compressed signal to the original signal. The higher the ratio the more the compressor will work.

Attack:

Basically, the attack determines how quickly the compressor kicks in after the track starts putting out signal. It's essentially the reaction time of the compressor.

Release:

The release is much like the attack but in reverse. It determines how quickly the compression stops once the signal drops below the threshold.

Make Up Gain:

The make-up gain or gain is used to turn the track up again to its original level. As compression makes the track quieter, this is a handy feature to bring it all back up again, without drastic dynamic movement.

Final Points and Tips:

Those are the most common and important features of a compressor, which work in unison to achieve the desired effect.

It's best to not use presets on a software compressor as doing it manually will serve you better in the long run. Especially if you move on to using hardware compressors in a studio as these will not have presets!

Most importantly, use your ears to determine if a track needs compression and how much compression reduces the desired dynamics without losing them completely.

Compression is one of those areas of music production that once you get it… you get it. It's not necessarily something you'll master overnight but once you understand the theory, it'll really help to put it into practice.