As opposed to interpreting a stereo audio signal or track as just ‘left’ and ‘right’, there are also the ‘middle’ and ‘sides’. The ‘middle’ refers to the sum of both left and right channels of a stereo image, whereas the ‘side’ refers to the signal difference between the left and the right channels. Having control over the middle and sides of an audio signal will allow for an overall wider result in a mix.
Mid/Side Processing is a technique where effects to the middle and sides of an audio signal. This technique can be utilised with a number of different plugins such as reverbs, EQs & compressors.
In the above video, Graham Cochrane from TheRecordingRevolution.com details how to use mid/side processing to control volume in the mastering stage of producing a studio recording. He specifically uses Center by Waves to adjust the mid and side volume levels separately, which results in a subtle, yet wider overall stereo image. Cochrane described the technique as a “life saver” for a recent project he had worked on.
Rory Dow from Sound On Sound mentions that “low‑frequency instruments such as kick drums and bass should be kept in the centre of the stereo field” due to our human brains not being able to detect where these frequencies are coming from easily. So mid/side processing can be used to isolate the low frequencies and keep them in the centre of the stereo field.
Having looked at this technique and the things that it can do in DAWs such as ProTools and Ableton, I’m able to relate it to a feature in FL Studio 11’s channel mixer. Underneath the panning control on every channel strip on the mixer is a control for ‘stereo separation’ with the unity/default level being in the middle. Turning it to the left 100% will separate the audio into left and right, while turning it 100% to the right will completely merge the signal into what feels like a mono signal. This is one way you can split a signal into seperate mid and side channels.
Another way to achieve mid/side routing is by using a feature in FL Studio called “Patcher”. Patcher allows you to visually route your plugins as if you were running outboard gear through an actual patch bay. The following video by FLStudioGuru from Image-Line (creators of FL Studio) explains how to achieve mid-side EQ processing using Patcher, Stereo Shaper, and two instances of Fruity Parametric EQ 2.
What a legend.
So in conclusion, not only mid/side processing is a simple concept to understand, but it is also very useful in bringing a somewhat stale mix back to life.
Cochrane, G. (2012, May, 22) Mid/Side Processing in Mastering [YouTube Video] Retrieved from http://www.youtube.com/watch?v=Sy84ctvSE8M
Dow, R. (2011, March) Creative Mid/Side Processing [Web Article] http://www.soundonsound.com/techniques/creative-midside-processing
Hillier, M. (2015, November, 23) Mastering Tutorial: Part Three – Mid-Side Processing Step-by-Step [Web Article] Retrieved from http://www.musictech.net/2015/11/mid-side-step-by-step/
Image-Line (2016, January, 7) FL Studio Guru | MID / SIDE EQ With Patcher [YouTube Video] Retrieved from http://www.youtube.com/watch?v=aEh-CQCNhCM
Stewart, R. (2015, August, 5) Mid/Side Stereo Explained: Part I [Web Article] Retrieved from http://www.justmastering.com/article-mid-side-stereo-explained-part1.php
Strongin, D. (2017, February, 3) 5 Mid/Side Processing Techniques To Improve Your Mix [Web Article] Retrieved from http://www.producerspot.com/best-tips-for-mid-side-processing-techniques
Tarr, E. (2015, July, 23) The Basics Of Mid-Side Processing [Web Article] Retrieved from, http://theproaudiofiles.com/mid-side-processing/