{"id":764,"date":"2015-04-01T00:09:00","date_gmt":"2015-04-01T00:09:00","guid":{"rendered":"http:\/\/box5722.temp.domains\/~audioor1\/audio-compression-intro-and-basics-part-2-sidechaining-2\/"},"modified":"2018-12-23T18:06:16","modified_gmt":"2018-12-23T18:06:16","slug":"audio-compression-intro-and-basics-part","status":"publish","type":"post","link":"https:\/\/audioordeal.co.uk\/audio-compression-intro-and-basics-part\/","title":{"rendered":"Audio Compression Intro and Basics – Sidechaining"},"content":{"rendered":"

In the\u00a0first post about audio compression<\/a>,\u00a0we looked at how a compressor will squeeze the volume above a certain level to create an overall louder sound. That was using compression<\/a> at it’s most basic. There is much more to it however, simple compression is great to tame an instrument or a mix but it can be used much more intelligently. Consider how with most electronic dance music, you get a loud pounding kick and a loud bass.<\/span><\/p>\n

These both occupy the same frequencies and can be very difficult to mix.<\/span>
\n
\n<\/i>When a dance song drops, you want the kick drum to be as loud as possible and you want the bass to be as loud as possible.<\/span><\/p>\n

Thing is if you have the kick as loud as it can be without going into the RED<\/span>\u00a0you are not going to have much room for anything else, let alone the bass.<\/span><\/p>\n

Likewise, if you have the bass maxing out the system, something as loud as a bassy club kick drum will take the volume far into the RED<\/span>.<\/span><\/p>\n

“Let’s just mix them together and slap on a compressor,” you say, after all, we now know that a compressor can reduce the volume to manageable levels.<\/span><\/p>\n

The bass will be loud and every time the kick plays, everything is reduced and fine…right?<\/span><\/p>\n

<\/div>\n
I would say it’s not wrong. There is an alternative, sidechain compression.<\/b><\/span><\/div>\n
<\/div>\n
In the club, we want really loud bass, however, when the kick plays, we need to realise it too holds a lot of bass frequencies.<\/span><\/div>\n
<\/div>\n
We don’t need both bass and kick sounding for the duration of the brief kick drum so we can lower the volume of the bass to make the kick sit nicely in it.<\/span><\/div>\n
<\/div>\n
Here is a diagram of how a sidechain compressor works:<\/span><\/div>\n
<\/a><\/span><\/div>\n
I often feel you need to understand the concept already for these diagrams to make sense, so if it is confusing, don’t panic.<\/i><\/span><\/div>\n
<\/div>\n
In normal compression, every time the track volume exceeds the set threshold, the compressor kicks in and reduces the volume of anything over that threshold.<\/span><\/div>\n
<\/div>\n
But we want to reduce the volume of the bass every time we hear the kick.<\/span><\/div>\n
<\/div>\n
So we can set the compressor to turn down bass every time the kick exceeds the threshold, without compressing the kick.<\/span><\/div>\n
<\/div>\n
For my example, I’m going to use\u00a0Reaper<\/a>‘s ReaComp, which comes natively to Reaper and is a compressor capable of sidechain compression.<\/span><\/div>\n
<\/div>\n
I am also aware that some of you won’t have great speakers or headphones on your person at all times so I will replace the bass with a mid-range chord pattern so you can hear the effect even if your listening device cannot reproduce sub-frequencies.<\/span><\/div>\n
<\/div>\n
<\/div>\n
<\/div>\n
On an important side note, this effect is not limited to bass frequencies or even kick drums. It also doesn’t require the kick drum to be heard in the song as it may not be sent to the master bus. a good example is in the Robin Schulz remix of “Prayer In C” at [1:42]<\/u><\/b> where there is a synth string section rhythmically dipping in volume. This is where an inaudible kick is activating the compressor and dipping the synth volume accordingly in time.<\/i><\/span><\/div>\n
<\/div>\n